Chapter 5 Resource: Motion, Forces, and Simple Machines

Comentarios

Transcripción

Chapter 5 Resource: Motion, Forces, and Simple Machines
Glencoe Science
Chapter Resources
Motion, Forces, and
Simple Machines
Includes:
Reproducible Student Pages
ASSESSMENT
TRANSPARENCY ACTIVITIES
✔ Chapter Tests
✔ Section Focus Transparency Activities
✔ Chapter Review
✔ Teaching Transparency Activity
✔ Assessment Transparency Activity
HANDS-ON ACTIVITIES
✔ Lab Worksheets for each Student Edition Activity
Teacher Support and Planning
✔ Laboratory Activities
✔ Content Outline for Teaching
✔ Foldables–Reading and Study Skills activity sheet
✔ Spanish Resources
✔ Teacher Guide and Answers
MEETING INDIVIDUAL NEEDS
✔ Directed Reading for Content Mastery
✔ Directed Reading for Content Mastery in Spanish
✔ Reinforcement
✔ Enrichment
✔ Note-taking Worksheets
Glencoe Science
Photo Credits
Section Focus Transparency 1: UNIVERSAL PRESS SYNDICATE
Section Focus Transparency 2: G. Savage/Vandtstadt/Photo Researchers
Section Focus Transparency 3: Jeff Greenberg/Visuals Unlimited
Teaching Transparency: (t) Lew Long/The Stock Market, (cl) Bob Daemmrich, (cr) Bob Daemmrich,
(b) Gregg Otto/Visuals Unlimited
Copyright © by The McGraw-Hill Companies, Inc. All rights reserved.
Permission is granted to reproduce the material contained herein on the condition
that such material be reproduced only for classroom use; be provided to students,
teachers, and families without charge; and be used solely in conjunction with the
Motion, Forces, and Simple Machines program. Any other reproduction, for use
or sale, is prohibited without prior written permission of the publisher.
Send all inquiries to:
Glencoe/McGraw-Hill
8787 Orion Place
Columbus, OH 43240-4027
ISBN 0-07-867198-1
Printed in the United States of America.
1 2 3 4 5 6 7 8 9 10 079 09 08 07 06 05 04
Table of Contents
To the Teacher
Reproducible Student Pages
■
iv
Hands-On Activities
MiniLAB: Try at Home Determining Weights in Newtons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
MiniLAB: Observing Mechanical Advantage–Pulleys. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Lab: Motion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Lab: Use the Internet Methods of Travel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Laboratory Activity 1: Speed of Falling Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Laboratory Activity 2: Newton’s First Law of Motion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Foldables: Reading and Study Skills . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
■
Meeting Individual Needs
Extension and Intervention
Directed Reading for Content Mastery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Directed Reading for Content Mastery in Spanish . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Reinforcement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Enrichment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Note-taking Worksheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
■
Assessment
Chapter Review. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Chapter Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
■
Transparency Activities
Section Focus Transparency Activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Teaching Transparency Activity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Assessment Transparency Activity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Teacher Support and Planning
Content Outline for Teaching. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T2
Spanish Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T5
Teacher Guide and Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T9
Additional Assessment Resources available with Glencoe Science:
•
•
•
•
•
•
•
•
•
ExamView® Pro Testmaker
Assessment Transparencies
Performance Assessment in the Science Classroom
Standardized Test Practice Booklet
MindJogger Videoquizzes
Vocabulary PuzzleMaker at msscience.com
Interactive Chalkboard
The Glencoe Science Web site at: msscience.com
An interactive version of this textbook along with assessment resources are available
online at: mhln.com
iii
To the Teacher
This chapter-based booklet contains all of the resource materials to help you teach
this chapter more effectively. Within you will find:
Reproducible pages for
■ Student Assessment
■ Hands-on Activities
■ Meeting Individual Needs (Extension and Intervention)
■ Transparency Activities
A teacher support and planning section including
■ Content Outline of the chapter
■ Spanish Resources
■ Answers and teacher notes for the worksheets
Hands-On Activities
Laboratory Activities: These activities do not require elaborate supplies or extensive pre-lab
preparations. These student-oriented labs are designed to explore science through a stimulating yet simple and relaxed approach to each topic. Helpful comments, suggestions, and
answers to all questions are provided in the Teacher Guide and Answers section.
Foldables: At the beginning of each chapter there is a Foldables: Reading & Study Skills
activity written by renowned educator, Dinah Zike, that provides students with a tool that
they can make themselves to organize some of the information in the chapter. Students may
make an organizational study fold, a cause and effect study fold, or a compare and contrast
study fold, to name a few. The accompanying Foldables worksheet found in this resource
booklet provides an additional resource to help students demonstrate their grasp of the
concepts. The worksheet may contain titles, subtitles, text, or graphics students need to
complete the study fold.
Meeting Individual Needs (Extension and Intervention)
Directed Reading for Content Mastery: These worksheets are designed to provide students
with learning difficulties with an aid to learning and understanding the vocabulary and
major concepts of each chapter. The Content Mastery worksheets contain a variety of formats
to engage students as they master the basics of the chapter. Answers are provided in the
Teacher Guide and Answers section.
iv
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
MiniLAB and Lab Worksheets: Each of these worksheets is an expanded version of each lab
and MiniLAB found in the Student Edition. The materials lists, procedures, and questions
are repeated so that students do not need their texts open during the lab. Write-on rules are
included for any questions. Tables/charts/graphs are often included for students to record
their observations. Additional lab preparation information is provided in the Teacher Guide
and Answers section.
Directed Reading for Content Mastery (in Spanish): A Spanish version of the Directed
Reading for Content Mastery is provided for those Spanish-speaking students who are
learning English.
Reinforcement: These worksheets provide an additional resource for reviewing the concepts of the chapter. There is one worksheet for each section, or lesson, of the chapter.
The Reinforcement worksheets are designed to focus primarily on science content and less
on vocabulary, although knowledge of the section vocabulary supports understanding of
the content. The worksheets are designed for the full range of students; however, they will
be more challenging for your lower-ability students. Answers are provided in the Teacher
Guide and Answers section.
Enrichment: These worksheets are directed toward above-average students and allow them
to explore further the information and concepts introduced in the section. A variety of
formats are used for these worksheets: readings to analyze; problems to solve; diagrams
to examine and analyze; or a simple activity or lab which students can complete in the
classroom or at home. Answers are provided in the Teacher Guide and Answers section.
Note-taking Worksheet: The Note-taking Worksheet mirrors the content contained in the
teacher version—Content Outline for Teaching. They can be used to allow students to take
notes during class, as an additional review of the material in the chapter, or as study notes
for students who have been absent.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Assessment
Chapter Review: These worksheets prepare students for the chapter test. The
Chapter Review worksheets cover all major vocabulary, concepts, and objectives
of the chapter. The first part is a vocabulary review and the second part is a concept review.
Answers and objective correlations are provided in the Teacher Guide and Answers section.
Chapter Test: The Chapter Test requires students to use process skills and understand content.
Although all questions involve memory to some degree, you will find that your students will
need to discover relationships among facts and concepts in some questions, and to use higher
levels of critical thinking to apply concepts in other questions. Each chapter test normally
consists of four parts: Testing Concepts measures recall and recognition of vocabulary and
facts in the chapter; Understanding Concepts requires interpreting information and more
comprehension than recognition and recall—students will interpret basic information and
demonstrate their ability to determine relationships among facts, generalizations, definitions,
and skills; Applying Concepts calls for the highest level of comprehension and inference;
Writing Skills requires students to define or describe concepts in multiple sentence answers.
Answers and objective correlations are provided in the Teacher Guide and Answers section.
Transparency Activities
Section Focus Transparencies: These transparencies are designed to generate interest
and focus students’ attention on the topics presented in the sections and/or to assess
prior knowledge. There is a transparency for each section, or lesson, in the Student Edition.
The reproducible student masters are located in the Transparency Activities section. The
teacher material, located in the Teacher Guide and Answers section, includes Transparency
Teaching Tips, a Content Background section, and Answers for each transparency.
v
Teaching Transparencies: These transparencies relate to major concepts that will benefit
from an extra visual learning aid. Most of these transparencies contain diagrams/photos
from the Student Edition. There is one Teaching Transparency for each chapter. The Teaching
Transparency Activity includes a black-and-white reproducible master of the transparency
accompanied by a student worksheet that reviews the concept shown in the transparency.
These masters are found in the Transparency Activities section. The teacher material includes
Transparency Teaching Tips, a Reteaching Suggestion, Extensions, and Answers to Student
Worksheet. This teacher material is located in the Teacher Guide and Answers section.
Assessment Transparencies: An Assessment Transparency extends the chapter content and
gives students the opportunity to practice interpreting and analyzing data presented in
charts, graphs, and tables. Test-taking tips that help prepare students for success on standardized tests and answers to questions on the transparencies are provided in the Teacher
Guide and Answers section.
Teacher Support and Planning
Content Outline for Teaching: These pages provide a synopsis of the chapter by section,
including suggested discussion questions. Also included are the terms that fill in the blanks
in the students’ Note-taking Worksheets.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Spanish Resources: A Spanish version of the following chapter features are included in this
section: objectives, vocabulary words and definitions, a chapter purpose, the chapter Activities, and content overviews for each section of the chapter.
vi
Reproducible
Student Pages
Reproducible Student Pages
■
Hands-On Activities
MiniLAB: Try at Home Determining Weights in Newtons . . . . . . . . . . 3
MiniLAB: Observing Mechanical Advantage–Pulleys. . . . . . . . . . . . . . . 4
Lab: Motion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Lab: Use the Internet Methods of Travel . . . . . . . . . . . . . . . . . . . . . . . . . 7
Laboratory Activity 1: Speed of Falling Objects . . . . . . . . . . . . . . . . . . . 9
Laboratory Activity 2: Newton’s First Law of Motion . . . . . . . . . . . . . 13
Foldables: Reading and Study Skills . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
■
Meeting Individual Needs
Extension and Intervention
Directed Reading for Content Mastery . . . . . . . . . . . . . . . . . . . . . . . . 17
Directed Reading for Content Mastery in Spanish . . . . . . . . . . . . . . . 21
Reinforcement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Enrichment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Note-taking Worksheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
■
Assessment
Chapter Review. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Chapter Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
■
Transparency Activities
Section Focus Transparency Activities . . . . . . . . . . . . . . . . . . . . . . . . . 42
Teaching Transparency Activity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Assessment Transparency Activity . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Motion, Forces, and Simple Machines
1
Hands-On Activities
Hands-On
Activities
2 Motion, Forces, and Simple Machines
Date
Class
Hands-On Activities
Name
Determining Weights in Newtons
Procedure
1. Stand on a bathroom scale and measure your weight.
2. Hold a large book, stand on the scale, and measure the combined weight of
you and the book. Record your data in the table below.
3. Repeat step 2 using a chair, heavy coat, and a fourth object of your choice.
Data and Observations
Pounds
Newtons
My weight
My weight
with a book
My weight
with a chair
My weight
with a coat
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
My weight with
a ____________
Analysis
1. Subtract your weight from each of the combined weights to calculate the weight of each object
in pounds.
2. Multiply the weight of each object in pounds by 4.4 to calculate its weight in newtons.
3. Calculate your own weight in newtons.
Motion, Forces, and Simple Machines
3
Name
Date
Class
Procedure
1. Tie a 3-m-long rope to the middle of a broomstick or dowel and hold this
stick horizontally. Another student should hold another stick horizontally.
Wrap the rope around both sticks four times, leaving about 0.5 m between
the sticks.
2. A third student should pull on the rope while the other two students try to
keep the sticks from coming closer together.
3. Observe what happens. Repeat using only two wraps of the rope and then
using eight wraps.
Analysis
1. Describe what you observed. Could the students hold the sticks apart?
2. Compare and contrast the results with two, four, and eight turns of the rope around the sticks.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Hands-On Activities
Observing Mechanical
Advantage—Pulleys
4 Motion, Forces, and Simple Machines
Name
Date
Class
Hands-On Activities
Motion
Lab Preview
Directions: Answer these questions before you begin the Lab.
1. Should you conduct this lab on a flat surface or on a hill?
2. For how long should you record the distance traveled by the ball at 1-s intervals?
What happens when you roll a small ball down a ramp? It speeds up as it
travels down the ramp, and then it rolls across the floor and eventually it
stops. You know that as the ball travels down the ramp, gravity is acting to
make it speed up. Think about the forces that are acting on the ball as it rolls
across the floor. Is there a net force acting on the ball? How would you describe
the motion of the ball?
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Real-World Question
How does a ball move when the forces acting on
it are balanced and when they are unbalanced?
Materials
small ball or marble
stopwatch
meterstick or tape measure
graph paper
Goals
■
■
Demonstrate the motion of a ball with
balanced and unbalanced forces acting on it.
Graph the position versus time for the
motion of the ball.
Safety Precautions
Procedure
1. Place the ball on the floor or a smooth, flat
surface.
2. Roll the ball across the floor by giving it a
gentle push.
3. Record Data As the ball is rolling and no
longer being pushed, have one student keep
track of the time and have other students
record the distance at 1-s intervals for at
least 5 s to 10 s.
4. Record anything else that you observed
about how the ball moved.
5. Calculate from your data the distance the
ball has traveled at each second.
6. Make a graph of the distance the ball
travels versus time. Plot the distance
traveled on the vertical y-axis and the time
on the horizontal x-axis.
7. Choose three one-second time intervals.
Calculate the speed of the ball in each of
those time intervals.
Motion, Forces, and Simple Machines
5
Name
Date
Class
(continued)
Conclude and Apply
1. Describe how the speed of the ball changes as it rolls along the floor.
2. Describe the forces acting on the ball before you pushed it and it was at rest. Infer whether the
forces acting on the ball were balanced or unbalanced.
3. Describe the forces acting on the ball as it rolled across the floor. Infer whether the forces
acting on the ball were balanced or unbalanced.
Communicating Your Data
Compare your graphs and results with those of other students in your class.
6 Motion, Forces, and Simple Machines
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Hands-On Activities
Data and Observations
Name
Date
Class
Use the Internet
Hands-On Activities
Methods of Travel
How long does it take you to get to the other side of town? How long does it
take to get to the other side of the country? If you were planning a road
trip from New York City to Los Angeles, how long would it take? How
would your trip change if you flew instead? When you plan a trip or vacation, it is useful to first estimate your travel time. Travel time depends on
the vehicle you use, how fast you travel, the route you take, and even the
terrain. For example, driving over rugged mountains can take longer than
driving over flat farmland. With this information, you can plan your trip
so you arrive at your final destination on time. Form a hypothesis about
what is the fastest form of travel.
Real-World Question
Make a Plan
What’s the fastest way to travel between two
specific locations?
1. Choose a starting point and a final
destination.
2. Identify the routes commonly used
between these two locations.
3. Determine the common forms of travel
between these two locations.
4. Research how to estimate travel time.
What factors can make your trip take more
or less time?
Goals
■
■
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
■
■
Research travel times.
Compare travel times for different methods
of travel.
Evaluate the fastest way to travel between
two locations.
Design a table to display your findings and
communicate them to other students.
Data Source
SCIENCEOnline Go to the Glencoe Science
Web site at msscience.com for more information on travel times, methods of travel, distances between locations, and data from other
students.
Follow Your Plan
1. Make sure your teacher approves your plan
before you start.
2. Calculate the travel time and distance
between your two locations for different
methods of travel.
3. Record your data on a separate sheet of
paper.
Analyze Your Data
1. Analyze the data recorded to determine the fastest method of travel. Was it better to drive or
fly? Did you investigate another method of travel?
Motion, Forces, and Simple Machines
7
Name
Date
Class
(continued)
3. Organize Data Use a computer (home, library, or computer lab) to create a chart that compares the travel times, average speeds, and distances for different methods of travel. Use your
chart to determine the fastest method of travel. What factors add to travel time?
Conclude and Apply
1. Compare your findings to those of your classmates and data posted on the Glencoe Science
Web site. What is the greatest distance investigated? The shortest?
2. Draw Conclusions What factors can affect travel time for the different methods? How would
your travel time be different if you didn’t have a direct flight?
3. Infer how the average speed of an airplane flight would change if you included your trips to
and from the airport and waiting time in your total travel time.
Communicating Your Data
Find this lab using the link below. Post your data in the table provided. Combine your data
with those of other students and make a class travel booklet that estimates travel times for
various locations around the world.
msscience.com
8 Motion, Forces, and Simple Machines
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Hands-On Activities
2. Calculate the average speed of the methods of travel you investigated. Which method had the
fastest speed? Which method had the slowest?
Date
1
Laboratory
Activity
Class
Speed of Falling Objects
Galileo attempted to prove that objects of different mass will reach the ground at the same time
when dropped from the same height. But this was difficult, since the objects fell so quickly he
couldn’t tell whether or not they actually hit the ground together. Galileo thought that if he could
slow down the objects, he would be able to make more accurate observations.
Strategy
You will show the speeds of falling objects of
different mass.
You will compare the speeds of falling objects
of different mass.
Materials
masking tape
15 cm × 150 cm gutter
*15 cm × 150 cm board with sides
chair
2 marbles (each of different mass)
index card
9. Exchange the position of the marbles at
the starting line and run the experiment
three more times (six times in all). Record
your results.
10. Repeat the experiment placing the gutter
at a different angle to the floor. Record
your results in Table 2.
Figure 1
*Alternate Materials
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Procedure
1. Place a strip of masking tape straight
across each end of the gutter (one near
each end of the board). See Figure 1.
2. Rest one end of the gutter on top of the
back of the chair. (The top of the gutter
should be at shoulder height or higher.)
See Figure 1.
3. Place both marbles on one edge of the tape at
the top of the gutter. This is the starting line.
4. Have your partner position himself or herself near the tape at the bottom. This is the
finish line.
5. Hold an index card in front of the marbles.
Raise it to release both marbles at the
same time.
6. Have your partner watch to see the order
in which the marbles cross the finish line.
7. Record the results by putting a checkmark
in the appropriate column in Table 1 in the
Data and Observations section.
8. Repeat the experiment two more times
with the marbles positioned as in step 3.
Motion, Forces, and Simple Machines
9
Hands-On Activities
Name
Name
Date
Class
Laboratory Activity 1 (continued)
Table 1
Slope _________________________
Trial
Large marble went faster
Small marble went faster
Both went at same speed
1
2
3
4
5
6
Table 2
Slope _________________________
Trial
Large marble went faster
Small marble went faster
Both went at same speed
1
2
3
4
5
6
Questions and Conclusions
1. How do the speeds of the rolling marbles compare?
2. Was there any difference in speed after you exchanged positions of the marbles?
10 Motion, Forces, and Simple Machines
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Hands-On Activities
Data and Observations
Name
Date
Class
Hands-On Activities
Laboratory Activity 1 (continued)
3. Why might it be important to change the position of the marbles for one half of the trials?
4. Compare and contrast your results with the ramp at different angles.
5. What can you conclude about the speed of falling objects of different mass?
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
6. Compare and contrast the motion of marbles rolling down the ramp with the motion of
marbles that are dropped.
Strategy Check
Can you show the speeds of falling objects of different mass?
Can you compare the speeds of falling objects of different mass?
Motion, Forces, and Simple Machines
11
Date
2
Laboratory
Activity
Class
Newton’s First Law of Motion
One of Isaac Newton’s laws of motion states that all bodies at rest tend to remain at rest unless
a force acts on them. However, once a body is set in motion by an outside force, the body moves
in a straight line until another force causes it to change speed or direction. The force that changes
the motion of the body may be air pressure, friction, or another body.
Strategy
You will measure the amount of force needed to set a body in motion.
You will deduce the relationship between the force needed to start a body in motion and the mass
of the body.
Materials
balance
bricks
spring scale
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Procedure
1. Determine the mass of one brick. Record it
in Table 1.
2. Attach the brick to the spring scale. Pull
the brick slowly across the floor.
3. Record the force needed to start the brick
in motion. Record the force needed to keep
the brick in motion.
4. Determine the mass of the second brick.
Add that to the mass of the first brick and
record it in Table 1.
5. Repeat steps 2 and 3 with the second brick
on top of the first brick.
6. Determine the mass of the third brick. Add
that to the mass of the other bricks and
record it in Table 1.
7. Repeat steps 2 and 3 with the third brick
on top of the other two bricks.
Data and Observations
Table 1
Number of bricks
Force (N)
Mass (kg)
Start
Keep in motion
1
2
3
Motion, Forces, and Simple Machines
13
Hands-On Activities
Name
Name
Date
Class
Laboratory Activity 2 (continued)
1. What is the outside force that starts the brick(s) in motion?
2. Compare the force needed to start the brick(s) in motion and the force needed to keep the
brick(s) in motion.
3. Compare the force required to keep the brick(s) in motion to the mass of the brick(s).
4. State the relationship between the force needed to start a body in motion and the body’s mass.
5. What force resists the motion of the bricks in all cases?
6. Explain in terms of Newton’s law of motion what happens to a passenger who is standing in
the aisle of a bus when the bus stops suddenly. Use diagrams to help explain your answer.
Strategy Check
Can you measure the amount of force needed to set a body in motion?
Can you state the relationship between the force needed to start a body in motion and
the mass of the body?
14 Motion, Forces, and Simple Machines
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Hands-On Activities
Questions and Conclusions
Name
Date
Class
Hands-On Activities
Motion, Forces, and Simple Machines
Directions: Use this page to label your Foldable at the beginning of the chapter.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Know
Want
Learned
Motion, Forces, and Simple Machines
15
Meeting Individual Needs
Meeting
Individual Needs
16 Motion, Forces, and Simple Machines
Name
Date
Directed Reading for
Content Mastery
Class
Overview
Motion, Forces,
and Simple Machines
Meeting Individual Needs
Directions: Use the formula v = d/t to answer the following question.
1. Julio rides his bike 12 km in 1.5 h. Determine the average speed at which Julio rode.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Directions: The figure below illustrates Newton’s third law of motion. Use it to answer the questions below.
2. Draw arrows on the figure above to show the direction in which the oars must
move to send the boat forward.
3. Do the arrows you drew in the figure represent an action force or a reaction force?
Directions: Answer the following question about weight.
4. If your weight is 490 N and you stand on a box that exerts a normal force of
440 N, what will happen?
Directions: Answer the following question on the lines provided.
5. A third-class lever has a mechanical advantage of less than one. Why are thirdclass levers used if this is the case?
Motion, Forces, and Simple Machines
17
Name
Date
Directed Reading for
Content Mastery
Section 1
Section 2
■
■
Class
Motion
Newton’s Laws
of Motion
Directions: Study the following diagram. Then answer questions 1 and 2 on the lines provided.
C
50 m
90 m
D
70 m
120 m
A
1. What distance will John travel if he goes from A to B to C to D and back again to A?
2. If John covers the distance in two minutes, what is his average speed in meters
per minute?
Directions: Write speed or acceleration to indicate what each unit below measures.
3. m/s
4. km/h
5. m/s/s
Directions: Fill in the blanks in the chart below.
Newton’s Laws of Motion
An object at rest will remain at rest or an object moving straight at constant
First law
speed will continue this motion until a 6. ____________________ acts on it.
An object that has a force acting on it will 7. ___________________ in the
Second law
direction of the force.
Third law
Forces always occur in equal but 8. ___________________ pairs.
18 Motion, Forces, and Simple Machines
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Meeting Individual Needs
B
Name
Date
Directed Reading for
Content Mastery
Section 3
■
Class
Work and Simple
Machines
Directions: Use the clues below to complete the puzzle.
Across
2. A machine that uses only one movement
4. The force you apply when using a machine
5. Probably the first simple machine
Meeting Individual Needs
Down
1. Work = force × _______
3. Inclined _______; ramp
Directions: Place a check mark (✓) next to each statement that is true. If the statement is false, rewrite the
statement to make it true.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
1. In order for you to do work, you only need to apply force to an object.
2. A simple machine is one that always gives a mechanical advantage of 2.
3. Force can be expressed in units called newtons.
4. An inclined plane allows you to lift a heavy load by using greater force
over less distance.
Motion, Forces, and Simple Machines
19
Name
Date
Directed Reading for
Content Mastery
Class
Key Terms
Motion, Forces,
and Simple Machines
Directions: Use the following terms to complete the sentences below.
joules
motion
output force
friction
acceleration
force
average speed
velocity
lever
net force
1. A push or a pull is a(n) ______________________________.
3. ______________________________ equals change in speed divided by time.
4. ______________________________ changes when speed changes, direction of
motion changes, or both factors change.
5. Work, like energy, is measured in ______________________________.
6. Mechanical advantage equals ______________________________ divided by
effort force.
7. ______________________________ equals total distance traveled divided by
travel time.
8. ______________________________ is a force that resists motion between two
surfaces that are in contact.
9. Probably the first simple machine invented by prehistoric humans was
the ______________________________.
10. The combination of all forces acting on an object is
the ______________________________.
20 Motion, Forces, and Simple Machines
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Meeting Individual Needs
2. Newton’s laws explain ______________________________.
Nombre
Fecha
Lectura dirigida para
Dominio del contenidio
Clase
Sinopsis
Movimiento, fuerzas
y máquinas simples
Satisface las necesidades individuales
Instrucciones : Usa la fórmula v = d/t para contestar la siguiente pregunta.
1. Julio anda en bicicleta 12 km en 1.5 h. Determina la rapidez promedio de Julio en
esta travesía.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Instrucciones: La figura ilustra la tercera ley del movimiento de Newton. Úsala para contestar las preguntas.
2. Dibuja flechas en la figura que muestren la dirección en que deben moverse los
remos para que el bote avance.
3. ¿Representan una fuerza de acción o una fuerza de reacción las flechas que
dibujaste?
Instrucciones: Contesta estas preguntas sobre el peso.
4. Si pesas 490N y estás parado sobre una caja que ejerce una fuerza normal de
440N, ¿qué sucederá?
Instrucciones: Contesta esta pregunta.
5. Una palanca de tercera clase tiene una ventaja mecánica de menos de uno. Si es
así, ¿por qué usamos palancas de tercera clase?
Movimiento, fuerzas y máquinas simples
21
Nombre
Fecha
Lectura dirigida para
Dominio del contenidio
Sección 1
Sección 2
Clase
■
■
El movimiento
Las leyes del
movimiento de Newton
Instrucciones : Estudia el diagrama. Contesta luego las preguntas 1 y 2 en los espacios dados.
C
50 m
B
70 m
120 m
A
1. ¿Qué distancia viajará John si va de A a B a C a D y de regreso a A?
2. Si John cubre esa distancia en dos minutos, ¿cuál es su velocidad promedio en
metros por minuto?
Instrucciones: Escribe velocidad o aceleración para indicar lo que mide cada unidad.
3. m/s
4. km/h
5. m/s/s
Instrucciones: Llena los espacios en blanco de la tabla.
Leyes del movimiento de Newton
Primera ley
Un cuerpo en reposo permanecerá en reposo y un cuerpo que se mueve en
línea recta a velocidad constante continuará este movimiento hasta que un(a)
6. ____________________ actúe sobre él.
Segunda ley
Un objeto que experimenta una fuerza actuando sobre él se
7. ___________________ en la dirección de la fuerza.
Tercera ley
Las fuerzas siempre ocurren en pares iguales pero 8. ___________________.
22 Movimiento, fuerzas y máquinas simples
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Satisface las necesidades individuales
90 m
D
Nombre
Fecha
Lectura dirigida para
Sección 3
Dominio del contenidio
Clase
■
Trabajo y
máquinas simples
Instrucciones : Usa las claves para completar el crucigrama.
1
3. Máquina que usa un solo movimiento
3
4. La fuerza que aplicas cuando usas
una máquina
2
Satisface las necesidades individuales
Horizontales
2. _______ inclinado; rampa
4
Verticales
1. Trabajo = fuerza × _______
2. Probablemente la primera máquina
simple
Instrucciones: Marca con una X la afirmación verdadera. Si la afirmación es falsa, vuelve a escribir la afirmación en forma correcta en las líneas dadas.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
1. Para realizar trabajo, sólo necesitas aplicarle una fuerza a un cuerpo.
2. Una máquina simple es aquella que siempre da una ventaja mecánica de dos.
3. La fuerza puede expresarse en unidades llamadas newtons.
4. Un plano inclinado permite levantar objetos pesados usando más fuerza
en una distancia más corta.
Motion, Forces, and Simple Machines
23
Nombre
Fecha
Lectura dirigida para
Dominio del contenidio
Clase
Términos claves
Movimiento, fuerzas y
máquinas simples
Instrucciones: Usa estos términos para completar las siguientes oraciones.
julios
fuerza de salida
fuerza
palanca
movimiento
fricción
velocidad promedio
fuerza neta
velocidad
1. Un empujón o un jalón es un(a) ______________________________.
2. Las leyes de Newton explican ______________________________.
3. El(La) ______________________________ es igual al cambio en velocidad
dividido por el tiempo.
4. El(La) ______________________________ cambia cuando cambia la velocidad, cuando cambia la dirección del movimiento, o cuando ambos(as) cambian.
5. Al igual que la energía, el trabajo se mide en
______________________________.
6. La ventaja mecánica es igual a ______________________________ dividida
por la fuerza de esfuerzo.
7. El(La) ______________________________ es igual a la distancia total recorrida dividida por el tiempo de viaje.
8. El(La) ______________________________ es la fuerza que resiste el
movimiento entre dos superficies en contacto.
9. Es posible que la primera máquina simple que inventaron los humanos prehistóricos haya sido el(la) ______________________________.
10. La combinación de todas las fuerzas que actúan sobre un cuerpo es el(la)
_____________________________.
24 Movimiento, fuerzas y máquinas simples
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Satisface las necesidades individuales
aceleración
Name
1
Date
Reinforcement
Class
Motion
Directions: Identify what each of the following formulas is used to find.
1. (change in speed)/time
2. acceleration × time
Meeting Individual Needs
3. (total distance traveled)/time
4. 1/2 (acceleration)(time)2
Directions: The graph shows the various speeds at which a worm travels over a 10-minute interval. Use the
graph to answer the questions that follow.
5. What is the greatest speed the worm reaches?
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
6. What is the worm’s acceleration during
the first 2 minutes?
7. How fast is the worm traveling as it goes
from A to B?
8. How far does the worm travel from A to B?
9. What is the worm’s acceleration from A to B?
10. How does the worm’s motion change from B to C?
11. What is the worm’s acceleration during the last 2 minutes?
12. How would you describe the worm’s motion during the last 2 minutes?
13. How far does the worm travel during the last 2 minutes?
Motion, Forces, and Simple Machines
25
Name
2
Date
Reinforcement
Class
Newton’s Laws of Motion
Directions: A yo-yo with a mass 0.25 kg is suspended from a hook on a ceiling. Use the diagram at the bottom
of the page to answer the questions.
1. Identify which of Newton’s laws explains what happens in each of the following steps.
a. Earth pulls the yo-yo downward
and the yo-yo pulls Earth upward.
b. The yo-yo doesn’t move.
d. The yo-yo keeps swinging
back and forth.
e. The yo-yo slows down
and eventually stops.
f. The yo-yo pulls on the hook and
the hook pulls on the yo-yo.
2. What is the net force acting on the yo-yo in step b?
3. In step e, what force causes the yo-yo to slow down and stop?
4. If a net force of 0.2 N is applied in step c, use the space below to calculate how fast the yo-yo
accelerates.
5. If the same net force is applied to a yo-yo with a mass of 0.5 kg, how will the rate of acceleration
be affected? Why?
6. If the hook exerts a force of 0.001
N on the ceiling, how much force
does the ceiling exert on the hook?
26 Motion, Forces, and Simple Machines
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Meeting Individual Needs
c. Someone pushes on the yo-yo in
the direction shown by the arrow,
and the yo-yo moves.
Name
3
Date
Class
Work and Simple Machines
Reinforcement
1. ____________________
2. ____________________
Meeting Individual Needs
Directions: Describe what is happening in each situation as work or no work.
3. ____________________
Directions: Name two situations in which no work is done to an object.
4.
5.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Directions: Answer the following questions on the lines provided.
6. What two things must occur for effort to count as work?
7. How is work measured?
8. What is mechanical advantage?
9. How do the three classes of levers differ?
10. How does a pulley make work easier if it doesn’t multiply force?
Motion, Forces, and Simple Machines
27
Name
1
Date
Enrichment
Class
The Art of Motion
Think back to the last time you read a comic book or saw a cartoon in the newspaper. Chances
are that somewhere in that comic strip, the cartoonist showed a character in motion. Do you
remember how it was done? Perhaps the cartoonist inserted horizontal lines to show motion.
Maybe the cartoonist altered the actual shape of an object. List three techniques for showing
motion in cartoons.
1.
3.
Directions: Using simple figures, motion lines, or other techniques, draw three cartoon panels of two
automobiles on a highway. One is moving at a constant speed and one is accelerating.
4. What formulas did your cartoon illustrate?
28 Motion, Forces, and Simple Machines
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Meeting Individual Needs
2.
Name
Enrichment
The Physics of Hitting
a Baseball
What does Newton have to do with hitting
a powerful homerun or line drive? According
to Alan Nathan, a physicist from the University of Illinois, understanding the laws of
physics can help batters improve their skill.
Some people believe that physical strength can
help send a ball sailing over the fence. Others
believe that hitting the ball with the “sweet
spot” of the bat, the place where batters feel
almost no vibration after a hit, is the best way
to score a home run. The laws of physics,
however, prove both theories to be false.
When ball meets bat, the impact from the
bat reverses the direction of the ball. Nathan
recommends imagining the ball as a spring and
the force between the bat and ball compressing
and then expanding, sending the ball flying.
However, the impact is extremely brief—less
than one-thousandth of a second. In that time,
some energy is lost to friction.
A Bigger Bat
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Class
In addition, because of the law of actionreaction, the ball exerts an opposite force on
the bat, causing the bat to move backward and
taking energy away from the spring motion
of the ball. Because of this fact, Nathan recommends using a heavier bat in order to
offset the backward movement after impact.
Furthermore, the impact causes some energy
to travel as vibrations along the wood or aluminum. Interestingly, the “sweet spot” that
many batters prefer because it causes the least
amount of vibration is not the ideal spot to
use for hitting the ball.
Finding the “Best Spot”
To find the best spot for hitting a baseball,
Nathan used a computer to perform calculations—formulas used to analyze the vibration
of airplane wings or bridges. The ideal spot he
was searching for would have to account not
only for vibrations, however, but also for the
circular motion of the bat as it strikes. That
motion increases the speed of the ball. The
results of his calculations are that with a 34inch bat, the best point of impact is about six
inches from the tip. With the help of another
researcher, Nathan was able to test his results
and found them to be accurate. Incidentally,
physical strength cannot help at this point in
the activity. All that matters, according to the
laws of physics, is the moment and point of
impact. Nathan states that “if the batter could
let go of the bat just prior to hitting the ball,
there would be no noticeable effect. The ball
would respond in exactly the same way.” Given
these findings, perhaps spring training will one
day include some work in the physics lab.
1. Which of Newton’s laws causes the bat to move back from the point of impact?
2. How do Newton’s other laws apply to this situation?
3. How might studying physics help people improve performance in other sports?
Motion, Forces, and Simple Machines
29
Meeting Individual Needs
2
Date
Name
Date
Bicycle Improvements
Enrichment
Meeting Individual Needs
The first bicycles did not have multiple
gears for ease of riding. Cyclists worked hard
to cover ground. They sat over the front
wheel because the pedals were attached
directly to the wheel’s axle. Rotating the pedals
once around moved the front wheel only one
complete revolution. The invention of the
chain drive allowed the rider to sit in a safer,
more balanced position between the front and
back wheels.
Gears
Later, the addition of gears with varying
ratios made it easier to ride up steep inclines
and pedal more efficiently. Gear ratios are figured by dividing the number of teeth in the
front sprocket by the number of teeth in the
rear sprocket. If there are 54 teeth in front and
27 in back, the ratio is 2 to 1 because 54 ÷ 27
= 2. This means that the rear sprocket goes
around twice each time the rider moves the
chain ring one complete revolution. If the rear
sprocket has 13 teeth, the ratio is about 4 to 1.
One turn of the pedals will rotate the back
sprocket four times. On downhills or level
ground, a rider doesn’t have to work as hard
to move the bicycle in the “fourth” gear as in
the “second.”
On the other hand, the steeper the incline,
the more difficult it is to ride a bike in a high
gear (think of lifting a heavy object straight up
instead of pushing it along a ramp). In this
case the rider’s goal is to easily turn the pedals
several times before the rear sprocket completes a revolution. The rider needs to shift
into a lower gear.
Chain Drives
Chain drives transfer the power from the
rider’s legs, which push down on the pedals
attached to levers (the cranks), which turn
the axle of the toothed wheel (front sprocket,
or chain ring). The chain is a continuous
loop attached to the chain ring and a rear
sprocket. As the chain ring rotates, it moves
the chain, which moves the rear sprocket,
which turns the rear wheel’s axle. Thus, the
invention of the chain drive meant that a
rider propelled the bike forward by moving
the rear wheel, not the front one. If you
think chain drives resemble pulley systems,
you’re right!
Directions: Complete the table below by computing the gear ratios (round to the nearest whole number).
Table 1
Gear
Number of teeth
in rear sprocket
Number of teeth
in front sprocket
a
11
60
1.
b
22
54
2.
c
41
84
3.
d
60
54
4.
Gear ratio
5. Which gear would be best for riding up a steep hill? Explain.
30 Motion, Forces, and Simple Machines
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
3
Class
Name
Date
Note-taking
Worksheet
Section 1
Class
Motion, Forces,
and Simple Machines
Motion
A. ______________ involves distance and time.
1. ________________ speed—calculated as total distance traveled divided by travel time
2. ______________________ speed—an object’s speed at a particular moment
3. When instantaneous speed does not change, an object is moving at _________________
4. Distance can be calculated if an object is moving at constant speed over a particular time
period; total distance traveled equals ______________________ times time.
B. Speed and direction of motion is _________________.
C. _____________________ is the change in velocity divided by the time needed for the change
to occur.
1. Acceleration can be calculated using a formula: acceleration equals change in
______________ divided by time.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
2. Acceleration can be shown on a speed-time graph.
Section 2
Newton’s Laws of Motion
A. ______________—a push or a pull
1. When a force acts on an object, it ________________ the object’s acceleration.
2. Two or more forces that cancel each other out are _________________ forces.
3. Two or more forces that do not cancel each other out are ___________________ forces.
4. The combination of all forces acting on an object is the ____________ force.
B. Newton’s _______________________—explain how forces cause motion
1. Newton’s first law—a moving object moves in a straight line with _________________
speed unless a force acts on it.
a. _________________—a force that resists movement between two surfaces in contact
b. An object’s tendency to resist a change in motion is ________________; the more mass
an object has, the greater its inertia.
Motion, Forces, and Simple Machines
31
Meeting Individual Needs
speed; average speed and instantaneous speed are the _____________ in this situation.
Name
Date
Class
Note-taking Worksheet (continued)
2. Newton’s second law—if an object is acted upon by a ____________ force, the change in
velocity will be in the direction of the ____________ force; acceleration can be calculated as
acceleration equals net force divided by mass.
3. Newton’s third law—forces always occur in equal but _________________ pairs; the equal
and opposite forces act on different objects, so they are not balanced forces.
Section 3
Work and Simple Machines
1. Occurs when a force causes an object to move in the same direction that the force is applied
2. Calculated as work equals ______________ times distance
B. A _______________ machine uses only one movement; a _________________ machine is a
combination of simple machines.
1. Mechanical __________________ is the number of times force is multiplied; calculated as
mechanical advantage equals output force divided by input force.
2. An ______________ machine would experience no friction, so work in would equal work out.
3. _____________ machines do experience friction, so work out is always less than work in.
C. ________________—an object with a groove, like a wheel, with a rope or chain running
through the groove; changes the direction of the input force
D. A lever is a rod or plank that pivots about a fixed point called the ________________.
1. The fulcrum is between the input force and the output force in a
____________________ lever.
2. In a _____________________ lever, the output force is between the input force and the
fulcrum.
3. The input force is between the output force and the fulcrum in a
____________________ lever
4. The ______________ and _____________ provide a mechanical advantage greater than one.
E. An _______________________ or ramp allows an object to be lifted over a greater distance
using less force.
1. A ______________ is a moving inclined plane with one or two sloping surfaces.
2. ______________—inclined plane wrapped around a post
32 Motion, Forces, and Simple Machines
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Meeting Individual Needs
A. _____________
Assessment
Assessment
34 Motion, Forces, and Simple Machines
Name
Date
Chapter
Review
Class
Motion, Forces,
and Simple Machines
Assessment
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Part A. Vocabulary Review
Directions: Write the term that matches each description below on the spaces provided. The heavily-boxed
letters will spell something for which Isaac Newton is famous.
1.
2.
3.
4.
5.
rate at which speed or direction changes
measures the quantity of matter
______ = force × distance
total distance divided by time
speed of an object and its direction
of motion
6. a push or pull
7. an inclined plane
8. force that resists motion between objects
in contact
9. speed of an object at any instant in time
10. the number of times your force is
multiplied
11. force that produces an acceleration
12. tendency to resist a change in motion
13. the boxed letters spell:
Motion, Forces, and Simple Machines
35
Name
Date
Class
Chapter Review (continued)
Part B. Concept Review
Directions: Fill in the blanks with the correct terms.
1. A machine that uses only one movement is a(n) ______________________________.
2. An object is accelerating if its ______________________________ or
______________________________ changes.
3. In a machine, the effort force you apply is used to overcome a
______________________________ force.
4. The speed of an object and its direction of motion are its
______________________________.
5. The speed of an object at any instant in time is its ______________________________ speed.
6. The less mass a moving object has, the _____________________________ it is to stop it.
7. Force pairs act on ______________________________ object(s).
8. A spring scale is used to measure ______________________________.
9. Machines can change the size of the force you apply, and/or change the
______________________________ of the force.
Assessment
11. The smoother a surface is, the ______________________________ the force of friction.
12. According to Newton’s second law, an object acted on by a net force will accelerate in the
direction of ______________________________.
13. If a person pushes on a wall with a force of 35 N, the force acting on the person
is ______________________________.
14. To do work, a(n) ______________________________ must be applied and the object must
move.
15. A ball dropped from a height of 125 m takes 5 s to hit the ground and is traveling at the rate
of 50 m/s when it hits.
a. The average speed of the ball in meters per second is ______________________________.
b. The ball’s acceleration is ______________________________.
c. After 3 seconds, the ball travels at a rate of ______________________________.
d. After 4 seconds, the ball has traveled a distance of ______________________________.
36 Motion, Forces, and Simple Machines
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
10. Friction always ______________________________ an object.
Name
Date
Chapter
Test
Class
Motion, Forces,
and Simple Machines
I. Testing Concepts
Directions: In the blank at the left, write the letter of the term that best completes each statement.
1. It would probably be easiest to ride a bicycle across ______.
a. a sidewalk
b. the grass
c. sand
d. gravel
2. The force that always acts opposite to the direction of the motion of an object is
called ______.
a. gravity
b. inertia
c. friction
d. none of these
3. According to Newton’s third law, forces always occur in ______ pairs.
a. equal but opposite
c. unequal but complementary
b. unequal but opposite
d. equal but complementary
4. Newton first described gravity while watching ______.
a. smoke rise
b. a car accelerate c. someone walking d. an apple falling
5. You would NOT use ______ to find the acceleration of an object.
a. time
b. initial speed
c. final speed
d. weight
6. Newton’s ______ law of motion explains why you may lean sideways in a car if the
driver turns a corner too quickly.
a. primary
b. first
c. second
d. third
d. Velocity
8. To calculate an average speed, you would use ______.
a. weight and time
c. acceleration
b. weight and distance
d. distance and time
Assessment
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
7. ______ is the speed of an object and its direction of motion.
a. Friction
b. Mass
c. Gravity
9. ______ is used to describe an object slowing down because of decreasing speed.
a. Acceleration
c. Negative acceleration
b. Average speed
d. Inertia
10. A bottle opener is a(n) ______.
a. first-class lever b. second-class lever c. third-class lever
d. inclined plane
11. An object that has a ______ will accelerate in the direction of the force.
a. normal force
b. net force
c. frictional force
d. speed
12. ______ is the rate at which an object covers a given distance.
a. Acceleration
b. Speed
c. Force
d. Motion
13. ______ is NOT a force.
a. Gravity
b. Mass
d. all of these
c. Friction
14. A 1-cm screw with a 4-cm thread would have a mechanical advantage of ______.
a. one
b. two
c. three
d. four
15. Stepping from a wagon and watching the wagon move away from you is an example
of Newton’s ______ law.
a. first
b. second
c. third
d. gravitational
Motion, Forces, and Simple Machines
37
Name
Date
Class
Chapter Test (continued)
Directions: Identify each statement as true or false. Rewrite false statements to make them correct.
16. Acceleration is a rate that can describe how speed or direction is changing.
17. A compound machine is a combination of simple machines.
18. A combination of pulleys increases the effort force, so the mechanical advantage is
greater than one.
19. Average speed does not include the time a car sits at red lights on the way home.
20. There is usually more friction on a smoother surface.
Directions: If the statement or term identifies a force, list its number under Force. If it does not identify a force,
list its number under Not a force.
Not a force
Assessment
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
the time it takes to make a trip
the mass of a person on a scale
the acceleration of a car turning a corner
friction
speed
color
taste
the weight of a person standing still
gravity
pushing your friend toward the door
38 Motion, Forces, and Simple Machines
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Force
Name
Date
Class
Chapter Test (continued)
II. Understanding Concepts
Skill: Making and Using Tables
Directions: Complete the table below by calculating the missing values.
Object
Initial speed
A
0 m/s
B
Final speed
Acceleration
4s
2 m/s
0 m/s
2s
-4 m/s
10 m/s
2s
1.
2.
0 m/s
C
Time
2
2
3.
4. Use the information in the table above to answer the following questions.
a. Which object has the greatest acceleration?
b. Which object has negative acceleration?
Assessment
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Skill: Concept Mapping
Directions: Complete the following concept map that describes what happens when a cue ball is struck by the
cue and then collides with the 8-ball.
cue strikes cue ball
cue ball
accelerates
cue ball strikes 8-ball
cue ball
5. ____________
cue ball rebounds
8-ball moves
opposite
6. ____________
7. ____________
in same direction
Motion, Forces, and Simple Machines
39
Name
Date
Class
Chapter Test (continued)
Skill: Designing an Experiment
8. How could you use a board and different materials found in the classroom to show the effect of
friction on a rolling marble?
III. Applying Concepts
Directions: Do the following calculations. Show your work on the lines provided.
1. What is the average speed of a car traveling 210 km in 3 h?
2. Calculate the distance an object travels if its speed is 60km/h and it travels for 6 h.
3. Calculate the mass of an object with a force of 20 N and an acceleration of 2 m/s2.
Assessment
5. Calculate the work of a weight lifter lifting a 400-N weight a distance of 2 m.
IV. Writing Skills
Directions: Answer the following questions using complete sentences.
1. According to Newton’s first law, if an arrow is shot in an open field, it should keep moving.
Explain why the arrow eventually stops.
2. Explain what inertia means.
40 Motion, Forces, and Simple Machines
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
4. Calculate the acceleration of an object that starts at rest and accelerates smoothly to 20 m/s in 5 s.
Transparency Activities
Transparency
Activities
Motion, Forces, and Simple Machines
41
Name
1
Date
Section Focus
Transparency Activity
Class
It Must Be Math
Calvin is right; calculating how fast you’re going is math. Whether
Calvin does it himself or a speedometer does it for him, a calculation
has to be made in order to find his speed.
CALVIN AND HOBBES © Watterson.
Reprinted with permission of UNIVERSAL PRESS SYNDICATE. All rights reserved.
2. Which method is best for measuring speed at a specific point on
the hill? Which method is best for comparing how quickly two
different sleds go down the hill?
3. Describe how the motion of the sled changes when it gets to the
bottom of the hill.
Transparency Activities
42 Motion, Forces, and Simple Machines
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
1. What two ways does the cartoon mention for measuring speed?
Name
2
Date
Section Focus
Transparency Activity
Class
Bird’s Eye View
1. How will the skydivers’ motion change when their parachutes
open?
Transparency Activities
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Skydiving is a sport that many people enjoy. Experienced jumpers
enjoy the feeling of free-fall before opening their parachutes. Working together, a team of skydivers can link arms to make formations
like the one you see.
2. Does their motion continue to change after their parachutes
open? Explain.
3. Would a heavier person fall more quickly than a lighter person?
Give a reason for your answer.
Motion, Forces, and Simple Machines
43
Name
3
Date
Section Focus
Transparency Activity
Class
Movin’ On
1. What do you see that helps the man move the boxes?
2. Where do you see wheels in this photograph?
Transparency Activities
3. If you had to load this truck with heavy boxes, what tools would
you want on hand?
44 Motion, Forces, and Simple Machines
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Moving is pretty hard work, but there are things that can help make
it easier. As you look at this picture, try to imagine what it would be
like if the man had only his bare hands to move the boxes.
Name
Teaching Transparency
Activity
Class
Newton’s Laws
of Motion
Transparency Activities
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
2
Date
Motion, Forces, and Simple Machines
45
Name
Teaching Transparency Activity
Date
Class
(continued)
1. If an object is accelerating, what can you infer about the forces acting on it?
2. What force set the ball in the top picture in motion? What force is slowing it down?
3. If the same force is applied to the refrigerator and the shopping cart, which will experience
greater acceleration? Why?
4. Which law of motion do the action and reaction arrows illustrate?
6. In the photo of the swimmer, you can see the action and reaction arrows are the same size.
Why don’t these forces cancel one another out?
Transparency Activities
46 Motion, Forces, and Simple Machines
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
5. When you walk, what is pushing against your foot?
Name
Date
Assessment
Transparency Activity
Class
Motion, Forces, and
Simple Machines
1. Newton’s third law says that forces act in opposing pairs. According to this information, what is the direction of the force the
railroad tracks exert on the train?
A1
B2
C3
D4
2. Which arrow indicates the force of friction?
F1
G2
H3
J4
Transparency Activities
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Directions: Carefully review the diagram and answer the following questions.
3. If the forces indicated by arrows 2 and 4 are the same size, which of
the following could describe the train’s motion?
A Speeding up before reaching a hill
B Slowing down as it approaches a downward slope
C Running along a straight track at a constant speed
D Applying the brakes slightly
Motion, Forces, and Simple Machines
47
Teacher Support
and Planning
Teacher Support and Planning
Content Outline for Teaching. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T2
Spanish Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T5
Teacher Guide and Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T9
Motion, Forces, and Simple Machines
T1
Section 1
Motion, Forces, and
Simple Machines
Motion
A. Speed involves distance and time.
Underlined words and
phrases are to be filled
in by students on the
Note-taking Worksheet.
1. Average speed—calculated as total distance traveled divided by
travel time
2. Instantaneous speed—an object’s speed at a particular moment
3. When instantaneous speed does not change, an object is moving at constant speed; average
speed and instantaneous speed are the same in this situation.
4. Distance can be calculated if an object is moving at constant speed over a particular time
period; total distance traveled equals average speed times time.
B. Speed and direction of motion is velocity.
C. Acceleration is the change in velocity divided by the time needed for the change to occur.
1. Acceleration can be calculated using a formula: acceleration equals change in speed divided by time.
2. Acceleration can be shown on a speed-time graph.
DISCUSSION QUESTION:
What two variables are involved in velocity? speed and direction of motion
Section 2
Newton’s Laws of Motion
A. Force—a push or a pull
1. When a force acts on an object, it changes the object’s acceleration.
2. Two or more forces that cancel each other out are balanced forces.
3. Two or more forces that do not cancel each other out are unbalanced forces.
4. The combination of all forces acting on an object is the net force.
B. Newton’s laws of motion—explain how forces cause motion
1. Newton’s first law—a moving object moves in a straight line with constant speed unless a
force acts on it.
a. Friction—a force that resists movement between two surfaces in contact
b. An object’s tendency to resist a change in motion is inertia; the more mass an object has,
the greater its inertia.
T2 Motion, Forces, and Simple Machines
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Teacher Support & Planning
Content Outline
for Teaching
2. Newton’s second law—if an object is acted upon by a net force, the change in velocity will
be in the direction of the net force; acceleration can be calculated as acceleration equals net
force divided by mass.
3. Newton’s third law—forces always occur in equal but opposite pairs; the equal and opposite
forces act on different objects, so they are not balanced forces.
DISCUSSION QUESTION:
How are mass and inertia related? The greater an object’s mass, the greater its inertia.
Section 3
Work and Simple Machines
A. Work
1. Occurs when a force causes an object to move in the same direction that the force is applied
2. Calculated as work equals force times distance
B. A simple machine uses only one movement; a compound machine is a combination of
simple machines.
1. Mechanical advantage is the number of times force is multiplied; calculated as mechanical
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
advantage equals output force divided by input force.
2. An ideal machine would experience no friction, so work in would equal work out.
3. Real machines experience friction, so work out is always less than work in.
C. Pulley—an object with a groove, like a wheel, with a rope or chain running through the
groove; changes the direction of the input force
D. A lever is a rod or plank that pivots about a fixed point called the fulcrum.
1. The fulcrum is between the input force and the output force in a first-class lever.
2. In a second-class lever, the output force is between the input force and the fulcrum.
3. The input force is between the output force and the fulcrum in a third-class lever
4. The wheel and axle provide a mechanical advantage greater than one.
E. An inclined plane or ramp allows an object to be lifted over a greater distance using less force.
1. A wedge is a moving inclined plane with one or two sloping surfaces.
2. Screw—inclined plane wrapped around a post
DISCUSSION QUESTION:
What is mechanical advantage? the number of times force is multiplied by a machine
Motion, Forces, and Simple Machines
T3
Teacher Support & Planning
Content Outline for Teaching (continued)
Movimiento, fuerzas
y máquinas simples
El movimiento
Lo que aprenderás
■
■
■
A definir velocidad y aceleración.
A relacionar la aceleración con el cambio de
velocidad.
A calcular distancia, velocidad y aceleración.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Vocabulario
average speed / velocidad media: tasa de
movimiento que se calcula dividiendo la distancia recorrida por la cantidad de tiempo que
se tarda en recorrer esa distancia.
velocity / velocidad: rapidez de un cuerpo y su
dirección de movimiento; cambia cuando
cambia la rapidez, cuando cambia la dirección
del movimiento o cuando las dos cambian.
instantaneous speed / velocidad instantánea:
rapidez de un objeto en cualquier momento
dado.
acceleration / aceleración: cambio en velocidad
dividido por la cantidad de tiempo que se
necesita para que ocurra el cambio; se presenta cuando un cuerpo acelera, decelera o
cambia de dirección.
Por qué es importante
El movimiento puede describirse usando la distancia, el tiempo, la velocidad y la aceleración.
Las leyes del movimiento
de Newton
Lo que aprenderás
■
■
■
A describir la forma en que las fuerzas afectan
al movimiento.
A calcular la aceleración usando la segunda
ley del movimiento de Newton.
A explicar la tercera ley del movimiento de
Newton.
Vocabulario
force / fuerza: un empuje o un jalón; el newton
es la unidad SI.
Newton’s laws of motion / leyes del
movimiento de Newton: conjunto de principios que explica el movimiento de los objetos.
friction / fricción: fuerza resistente al movimiento entre dos superficies que se tocan y
que siempre actúa opuesta a la dirección del
movimiento.
inertia / inercia: tendencia a resistir un cambio
en movimiento.
Por qué es importante
Las leyes de Newton explican movimientos tan
simples como caminar y tan complicados como
el lanzamiento de un cohete.
Trabajo y máquinas simples
Lo que aprenderás
■
■
■
A definir trabajo.
A distinguir los diferentes tipos de máquinas
simples.
A explicar cómo las máquinas facilitan el
trabajo.
Vocabulario
work / trabajo: se lleva a cabo cuando una
fuerza aplicada causa el movimiento de un
cuerpo en la dirección de la fuerza.
simple machine / máquina simple:
dispositivo que facilita el trabajo con un
movimiento solamente; puede cambiar el
tamaño o la dirección de una fuerza; entre
este tipo de máquina se incluyen la cuña,
el tornillo, la palanca, la rueda y eje, la
polea y el plano inclinado.
compound machine / máquina compuesta:
combinación de dos o más máquinas simples.
mechanical advantage / ventaja mecánica:
número de veces que una máquina multiplica
la fuerza de esfuerzo que se le aplica.
pulley / polea: máquina simple compuesta de
una rueda acanalada con una cuerda, cadena o
cable que corre a lo largo de una ranura; una
polea cambia la dirección de la fuerza de
esfuerzo y puede ser fija o movible.
lever / palanca: máquina simple hecha de una
barra libre para girar sobre un punto fijo.
Movimiento, fuerzas y máquinas simples
T5
Teacher Support & Planning
Spanish
Resources
inclined plane / plano inclinado: máquina simple
que consta de una superficie inclinada, como
una rampa, que reduce la cantidad de fuerza
que se necesita para levantar algo, al aumentar
la distancia sobre la cual se aplica la fuerza.
Por qué es importante
Las máquinas facilitan el trabajo.
Movimiento
¿Qué sucede cuando dejas rodar una pelota
pequeña por una rampa? La pelota acelera al
bajar la rampa, luego rueda por el piso y finalmente se detiene. Sabes que a medida que baja
por la rampa, la gravedad actúa para acelerar la
pelota. Piensa en las fuerzas que están actuando
sobre la pelota al rodar sobre el piso. ¿Actúa
una fuerza neta sobre la pelota? ¿De qué manera describirías el movimiento de la pelota?
Preguntas del mundo real
¿Cómo se mueve la pelota cuando las fuerzas
que actúan sobre ella están equilibradas y
cuando no están equilibradas?
Materiales
pelota pequeña o canica
metro o cinta métrica
cronómetro
papel para graficar
Metas
■ Demostrar el movimiento de una pelota
sobre la que actúan fuerzas equilibradas y
desequilibradas.
■ Graficar la posición de la pelota con relación
al tiempo.
Medidas de seguridad
Procedimiento
1. Coloca la pelota sobre el piso o una superficie plana y lisa.
2. Rueda la pelota por el piso empujándo la
suavemente.
T6 Movimiento, fuerzas y máquinas simples
3. Anota datos Cuando la pelota ya ruede sola
haz que un alumno anote el tiempo y que
otros anoten la distancia a intervalos de 1 s
durante 5 ó 10 s.
4. Escribe todo lo que observes sobre el
movimiento de la pelota.
5. Calcula la distancia que la pelota recorrió
cada segundo.
6. Has un gráfico de la distancia que la pelota
viajó versus el tiempo. Dibuja la distancia
recorrida en el eje de y vertical y el tiempo
en el eje de horizontal.
7. Escoge tres intervalos de un segundo.
Calcula la velocidad de la pelota en cada
uno de esos intervalos.
Concluye y aplica
1. Describe cómo cambió la velocidad de la
pelota a medida que rodaba por el piso.
2. Describe las fuerzas que actuaron sobre la
pelota antes de empujarla, cuando estaba en
reposo. Infiere si las fuerzas que actuaron
sobre ella eran equilibradas o desequilibradas.
3. Describe las fuerzas actuando sobre la
pelota a medida que rodaba por el piso.
Infiere si las fuerzas que actuaron sobre ella
eran equilibradas o desequilibradas.
Comunica tus datos
Compara tus gráficos con los de otros
estudiantes de tu clase.
Usa Internet
Métodos de viaje
Preguntas del mundo real
¿Cuánto tiempo te toma llegar al otro lado de la
ciudad? ¿Cuánto tiempo toma llegar al otro
lado del país? ¿Si estuvieras planeando un viaje
de la ciudad de Nueva York a Los Ángeles,
¿cuánto tiempo se necesitaría? ¿Cómo cambiaría tu viaje si volaras? Cuando planeas un
viaje de vacaciones, es útil estimar antes el
tiempo de viaje. El tiempo de viaje depende del
vehículo que usas, qué tan rápido viajas, la ruta
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Teacher Support & Planning
Spanish Resources (continued)
que tomes y hasta el terreno. Por ejemplo,
manejar sobre montañas escabrosas puede
llevar más tiempo que manejar por regiones
agrícolas planas. Con esta información, puedes
planear tu viaje de tal manera que llegues a
tiempo a tu destino final. Formula una hipótesis
sobre cuál es la forma más rápida de viajar.
Metas
Investigar tiempos de viaje.
■ Comparar tiempos de viaje en diferentes
medios de transporte.
■ Evaluar la manera más rápida de viajar entre
dos puntos.
■ Diseñar una tabla para mostrar tus hallazgos
y comunicarlos a otros alumnos.
■
Fuente de datos
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Visita red.msscience.com/
internet_lab para más
información sobre tiempos de viaje, medios de
transporte, distancias entre lugares y datos de
otros estudiantes.
Diseña un plan
1. Escoge un punto inicial y un destino final.
2. Identifica las rutas que se usan comúnmente entre esas dos localidades.
3. Estudia los medios comunes de viajar entre
esas dos localidades.
4. Investiga cómo estimar el tiempo de viaje.
¿Qué factores pueden hacer que tu viaje
dure más o menos tiempo?
Sigue tu plan
1. Asegúrate de que tu maestro(a) apruebe tu
plan antes de comenzar.
2. Calcula el tiempo de viaje y la distancia
entre tus dos localidades usando diferentes
medios de transporte.
Analiza tus datos
1. Analiza los datos que anotaste en tu Diario
de ciencias para determinar el método más
rápido de viajar. ¿Qué es mejor, manejar o
volar? ¿Investigaste otro método de viaje?
2. Calcula la velocidad promedio para los
medios de transporte que investigaste. ¿Cuál
es el más rápido? ¿Cuál es el más lento?
3. Haz una tabla que compare el tiempo de
viaje, la rapidez promedio y las distancias de
los diferentes métodos de viaje. ¿Cuál es el
método más rápido? ¿Es este siempre el más
conveniente? ¿Qué factores aumentan el
tiempo de viaje?
4. Comparte tus datos poniéndolos en el sitio
Web de Glencoe Science.
Concluye y aplica
1. Compara tus hallazgos con los de tus compañeros y con los datos publicados en el
sitio Web de Glencoe Science. ¿Cuál fue la
mayor distancia investigada? ¿La menor?
2. ¿Qué factores pueden afectar el tiempo de
viaje de cada medio? ¿Cómo variaría tu
tiempo de viaje si no hubieras tenido un
vuelo directo?
3. Infiere cómo el promedio de velocidad de
un vuelo cambiaría si en el tiempo total de
viaje incluyeras la ida y el regreso al aeropuerto y los tiempos de espera.
Comunica tus datos
Halla este laboratorio usando el enlace
red.msscience.com/internet_lab. Publica tus
datos en la tabla provista. Combina tus datos
con los de otros estudiantes y haz un cuaderno
de viajes que estime el tiempo de viaje para
varias localidades alrededor del mundo.
Guía de estudio
Sección 1 El movimiento
1. La velocidad promedio es la distancia recorrida dividida por el tiempo: s d/t
2. Un objeto está acelerando cuando su velocidad y/o dirección de movimiento cambia.
3. La aceleración puede calcularse al dividir el
cambio de velocidad por el tiempo.
Sección 2 Las leyes del movimiento de Newton
1. Inercia es una medida de la dificultad para
alterar el movimiento de un cuerpo.
Movimiento, fuerzas y máquinas simples
T7
Teacher Support & Planning
Spanish Resources (continued)
2. La primera ley de Newton establece que un
cuerpo permanecerá en reposo o moviéndose con velocidad constante si no actúa
ninguna fuerza sobre él.
3. La segunda ley de Newton describe la manera en que las fuerzas desequilibradas o las
fuerzas netas actúan sobre un cuerpo. El
cuerpo acelerará de acuerdo con Fnet = ma.
4. La tercera ley de Newton establece que las
fuerzas actúan en pares iguales pero
opuestos.
Sección 3 Trabajo y máquinas simples
1. Se hace trabajo cuando una fuerza hace que
un cuerpo se mueva en la dirección de la
fuerza. El trabajo es igual a la fuerza aplicada
multiplicada por la distancia sobre la que se
aplica la fuerza.
2. Una máquina es un instrumento que hace
más fácil el trabajo. Una máquina simple
facilita el trabajo con un movimiento. Una
máquina puede aumentar la fuerza, aumentar la distancia o cambiar la dirección de la
fuerza aplicada. ¿Cómo facilita el trabajo esta
palanca?
3. Ventaja mecánica es la fuerza de resistencia
dividida por la fuerza de esfuerzo.
4. Los seis tipos de máquinas simples son:
plano inclinado, cuña, tornillo, palanca,
rueda y eje, y polea. Una máquina compuesta está hecha de máquinas simples.
T8 Movimiento, fuerzas y máquinas simples
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Teacher Support & Planning
Spanish Resources (continued)
Hands-On Activities
MiniLAB: Try at Home (page 3)
1. Answers will vary.
2. Answers will vary.
3. Answers will vary.
MiniLAB: (page 4)
1. Students will observe that it is nearly impossible
to prevent the sticks from being pulled together.
2. The more times the rope is wrapped around the
sticks, the harder it is to keep the sticks from
being pulled together.
Lab (page 5)
Lab Preview
1. flat surface
2. for at least 5 s to 10 s
Conclude and Apply
1. The ball slows down and comes to a stop.
2. Gravity and static friction; because the ball’s
motion did not change, no unbalanced force was
acting on it.
3. Gravity and rolling friction; friction was the
unbalanced force that caused the motion of the
ball to change.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Lab: Use the Internet (page 7)
Analyze Your Data
1. Answers will be subjective and based on the
students’ individual research.
2. Remind students that speed is calculated by
dividing distance traveled by amount of time for
the trip.
3. Students might conclude that the fastest method
might not always be the most convenient. Factors
such as flight schedules may influence their
decisions.
Conclude and Apply
1. Answers will vary based on each student’s
individual research.
2. Weather conditions and time of day can affect
travel times. Layovers can significantly add to
travel time.
3. Average speed would decrease, as the time spent
traveling to and from airports as well as waiting
time can be significant.
Questions and Conclusions
1. Students should find that the speeds are similar.
2. If the gutter is level, there should not be any
apparent difference in speed.
3. Answers will vary. It is important to find out that
position in the gutter is not a factor in regard to
speed.
4. Students should find the results are the same no
matter what the angle.
5. Objects of different mass fall at the same rate of
speed.
6. Answers may vary but should include that the
friction of the ramp will slow the marbles more
than the friction of the air will.
Laboratory Activity 2 (page 13)
Data and Observations
Answers will vary depending on the accuracy of student measurements.
Questions and Conclusions
1. the hand pulling on the brick
2. The force needed to start the brick is greater than
the force needed to keep the brick in motion.
3. The greater the mass of the brick, the greater the
force needed to keep the brick in motion.
4. The greater the mass of a body, the greater the
force needed to start a body in motion.
5. friction
6. The person inside the bus is moving with the
speed of the bus. When the bus stops, the person
will continue to move forward because of inertia.
Meeting Individual Needs
Directed Reading for Content Mastery (page 17)
Overview (page 17)
1. 8 km/h
2.
Laboratory Activity 1 (page 9)
Data and Observations
Tables 1 and 2 should show most or all marks in the
last column, indicating both marbles fell at the same
speed.
Motion, Forces, and Simple Machines
T9
Teacher Support & Planning
Teacher Guide
& Answers
3. action force
4. The box will collapse.
5. They increase the distance over which the force is
applied, so you don’t need as much force.
Sections 1 and 2 (page 18)
1. 120 m + 90 m + 50 m + 70 m = 330 meters
2. 330 m ÷ 2 min = 165 meters per minute
3. speed
4. speed
5. acceleration
6. net force
7. accelerate
8. opposite
Section 3 (page 19)
1
Lectura dirigida para Dominio del contenido (pág. 21)
Sinopsis (pág. 21)
1. 8 km/h
2.
3
D
P
2
S I M P L E
S
A
4
T
I N P U T
A
E
N
C
5
L E V E R
1. Force must be applied to an object and that
object must move in the direction of the applied
force to perform work.
2. A simple machine is one that has only one part.
3. √
4. An inclined plane allows you to lift a heavy load
by using less force over greater distance.
Key Terms (page 20)
1. force
2. motion
3. acceleration
4. velocity
5. joules
6. output force
7. average speed
8. friction
9. lever
10. net force
T10 Motion, Forces, and Simple Machines
3. acción fuerza
4. La caja se hundirá.
5. Aumentan la distancia sobre la cual se aplica la
fuerza, de modo que no necesitas tanta fuerza.
Secciones 1 y 2 (pág. 22)
1. 120 m + 90 m + 50 m + 70 m = 330 metros
2. 330 m ÷ 2 min = 165 metros por minuto
3. rapidez
4. rapidez
5. aceleración
6. fuerza neta
7. acelera
8. opuesto
Sección 3 (pág. 23)
1
2
D
I
3
S
L
A
N
O
R
A
D
A
I
M P
T
A
P
L
E
A
4
E
N
N
C
C
A
T
A
I
A
1. La fuerza se debe aplicar al cuerpo y ese cuerpo
debe moverse para realizar trabajo.
2. Una máquina simple es aquella que sólo consta de
una parte.
3. X
4. Un plano inclinado te permite levantar una carga
pesada al usar menos fuerza a lo largo de una distancia mayor.
Términos claves (pág. 24)
1. fuerza
2. movimiento
3. aceleración
4. velocidad
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Teacher Support & Planning
Teacher Guide & Answers (continued)
5.
6.
7.
8.
9.
10.
julios
fuerza de salida
rapidez promedio
fricción
palanca
fuerza neta
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Reinforcement (page 25)
Section 1 (page 25)
1. acceleration
2. speed at a given time
3. average speed
4. distance traveled
5. 25 cm/min
6. 5 cm/min2
7. 10 cm/min
8. 30 cm
9. 0
10. it accelerates
11. (0 cm/min – 25 cm/min)/2 min = 12.5 cm/min2
12. negative acceleration
13. 1 (12.5)(2)2 = 25 cm
2
Section 2 (page 26)
1. a. third law
b. first law
c. second law
d. first law
e. second law
f. third law
2. 0
3. friction
4. a = Fnet/m
a = (0.2 N)/(0.25 kg) = 0.8 m/s2
5. The yo-yo will not accelerate as quickly; the larger
the mass, the smaller the acceleration for the same
amount of force.
6. 0.001 N
Section 3 (page 27)
1. no work
2. no work
3. work
4–5. The object does not move. The object does not
move in the same direction as the force.
6. You must apply force to an object, and the
object must move in the same direction as the
force you apply.
7. Work is measured in joules, Students may give
the formula, 1 J = 1 N • m
8. the number of times a force is multiplied
9. They depend on the position of the fulcrum and
the effort force and resistance force. In a firstclass lever, the fulcrum is between the effort
force and resistance force. In a second-class
lever, the resistance force is in the middle. In a
third-class lever, the effort force is in the middle.
10. It changes the direction of the force.
Enrichment (page 28)
Section 1 (page 28)
1–3. Answers may include billowing clothing,
depicting two or more versions of the character in
the same panel as, for instance, the character
swings on a vine, or over several panels showing
people frozen in the background as the character
races past.
Cartoon panels: Answers will vary. Panel 1 may
present Car A behind Car B, in panel 2 they may
be even, and in panel 3 Car A may be pulling
ahead. Students may include long vertical motion
lines to simulate speed. They may even change the
shape of the car to show that one is “working
harder” to pass the other.
4. The first, constant motion, represents the formula
speed = d/t.
The second, accelerating motion, represents the
formula a = (final speed – initial speed)/t.
Section 2 (page 29)
1. Newton’s second law of motion
2. The ball would continue moving in a straight line
until another force, such as the bat or gravity,
changed its direction. The force and acceleration
both come from the same place—the point of
impact on the bat.
3. Answers will vary.
Section 3 (page 30)
1. 5:1
2. 2:1
3. 2:1
4. 1:1
5. Gear d has the lowest ratio. It would be the best
gear for riding uphill.
Note-taking Worksheet (page 31)
Refer to Teacher Outline, student answers are
underlined.
Assessment
Chapter Review (page 35)
Part A. Vocabulary Review (page 35)
1. acceleration (2/1)
2. mass (5/2)
3. work (7/3)
4. average speed (3/1)
5. velocity (1/1)
6. force (4/2)
7. ramp (8/3)
8. friction (5/2)
9. instantaneous speed (1/1)
10. mechanical advantage (9/3)
11. net force (4/2)
12. inertia (4/2)
13. laws of motion (4/2)
Motion, Forces, and Simple Machines
T11
Teacher Support & Planning
Teacher Guide & Answers (continued)
Part B. Concept Review (page 36)
1. simple machine (8/3)
2. speed, direction (1/1)
3. resistance (9/3)
4. velocity (2/1)
5. instantaneous (1/1)
6. easier (5/2)
7. different (6/2)
8. mass (5/2)
9. direction (9/3)
10. slows (2/1)
11. smaller (4/2)
12. the force (5/2)
13. 35 N (4/2)
14. force (7/3)
15. a.125 m/5 s = 25 m/s (3/1)
b. (50 m/s)/5 s = 10 m/s2 (3/1)
c. (10 m/s2) ✕ 3 s = 30 m/s (3/1)
d. 1/2(10 m/s2)(4 s)2 = 80 m (3/1)
Chapter Test (page 37)
I.
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
Testing Concepts (page 37)
a (4/2)
c (4/2)
a (6/2)
d (4/2)
d (2/1)
b (4/2)
d (2/1)
d (3/1)
c (2/1)
a (8/3)
b (4/2)
b (1/1)
b (5/2)
d (9/3)
c (6/2)
true (1, 2/1)
true (9/3)
true (8/3)
false; Average speed does include the time a car
sits at red lights on the way home. (3/1)
20. false; There is usually less friction on a smooth
surface. (4/2)
21–30. Force—23, 24, 28, 29, and 30
Not a force—21, 22, 25, 26, and 27 (4/2)
II. Understanding Concepts (page 39)
1. 8 m/s (3/1)
2. 8 m/s (3/1)
3. 5 m/s2 (3/1)
4. a. C (3/1)
b. B (3/1)
5. slows down (4/2)
6. reaction or direction (4/2)
7. accelerates (4/2)
T12 Motion, Forces, and Simple Machines
8. Answers will vary. One possible experiment would
use the board as an inclined plane to consistently
accelerate the marble. Materials at the base of the
board could include concrete, linoleum, carpet,
water, metal, wood, or sand. An accurate means of
measuring time would also be necessary. (4/2)
III. Applying Concepts (page 40)
1. s = d/t = 210 km/3 = 70 km/h (3/1)
2. d = s ✕ t = 60 km/h ✕ 6 h = 360 km (3/1)
3. F = m ✕ a; 20 = m ✕ 2; m = 20/2 = 10 kg (5/2)
4. a = (final speed – initial speed)/t = 20 – 0/5 =
4 m/s2 (5/2)
5. W = F ✕ d = 400 N ✕ 2 m = 800 N m = 800 joules
or 800 J (7/3)
IV. Writing Skills (page 40)
1. Gravity acts on the arrow, causing it to fall.
Students may also know that air friction slows the
arrow. (4/2)
2. Inertia is a tendency to resist a change in motion.
Students may know that inertia is the measure of
an object’s ability to stay at rest or to keep in
motion. (4/2)
Section Focus Transparency 1 (page 42)
It Must Be Math
Transparency Teaching Tips
Ask the students why it’s important to know
your speed while driving a car. The speedometer
display is connected to the transmission and
computes speed relative to the turning rate of the
driveshaft. Explain the practical elegance of being
able to compute the movement of real objects
using numbers.
■ Ask students to explain what Hobbes means in
the second panel of the cartoon strip.
■ Provide the students the following data and ask
them to find the final speed in miles per hour.
The distance traveled was 450 feet; the time was
ten seconds. Remind them that after finding
feet/second, they will have to change it to
miles/hour. Tell them that they will need to
complete four steps to solve the problem.
(450 ÷ 10 = 45; 45 ✕ 60 = 2,700; 2,700 ✕ 60 =
162,000; 162,000 ÷ 5280 = 30.68, or around 31
miles per hour.) Using metrics and a distance of
137 meters, the math is as follows: 137 ÷ 10=13.7
× 60 = 822; 822 × 60 = 49,320; 49,320 ÷ 1000 =
49.32, or around 49 kilometers per hour. Make
this as fun and easy as possible.
Content Background
■ Besides driving, measuring speed is important in
all forms of transportation. It is also used in
predicting weather, numerous athletic events, and
in science.
■ In luge, a form of sledding, speeds greater than
120 km/h (75 mph) have been attained.
■ Speed equals distance traveled divided by time.
■
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Teacher Support & Planning
Teacher Guide & Answers (continued)
Answers to Student Worksheet
1. The cartoon mentions a speedometer and
dividing distance by time.
2. The speedometer is best for getting the speed at a
specific instant. On the other hand, average speed
(distance divided by time) tells you which sled
descended the hill more quickly.
3. Friction and some air resistance stop the sled.
Section Focus Transparency 2 (page 43)
Bird’s Eye View
Transparency Teaching Tips
You may use this transparency to introduce gravity
as a force. According to Newton’s law of gravitation,
every object in the universe attracts every other
object (the exact mechanics at the atomic level are
not yet understood). Tell the students that the
greater the mass of the attracting object, the more
force is applied. Drop a small book and a ruler and
have students observe. Ask them why they landed at
the same time. (The Earth’s gravitational pull is
constant, the same for both.)
■ Ask the students whether skydivers fall at everincreasing speeds or at a constant rate as they
hurtle earthward.
■ Ask the students why body position affects rate of
descent (surface area exposed to air resistance).
Content Background
■ The gravitational attraction (force) between two
bodies is proportional to the mass of each, varying
inversely to the square of the distance between
them.
■ On Earth, a falling object accelerates from a resting
position to terminal velocity, which is the fastest
free-fall velocity. A skydiver accelerates in the
direction of the force, or toward Earth. Terminal
velocity for a skydiver is around 193 meters per
second.
■ Earth’s gravitational force keeps the Moon in
orbit. This force is actually causing the Moon to
fall, not toward the Earth but from the straight
line it would travel if gravity were not at work.
■ The first verifiable parachute jump was successfully completed in 1797 by the Frenchman
Andre-Jacques Garnerin. He jumped from a
balloon 1,000 meters (almost 3,300 feet) over
Paris.
Answers to Student Worksheet
1. The skydivers fall with increasing speed, attracted
by the gravitational pull of Earth. Opening the
parachute slows the rate of descent and allows the
skydivers to land safely.
2. Opening the parachute causes an acceleration,
slowing the skydivers’ fall. If a skydiver changes
direction during a fall, that is another acceleration.
3. They fall at the same rate because the gravitational
pull of Earth is constant (the same for everyone).
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
■
Section Focus Transparency 3 (page 44)
Movin’ On
Transparency Teaching Tips
You may use this transparency to introduce simple machines. Point out and briefly explain the six
simple machines—lever, pulley, wheel and axle,
inclined plane, screw, and wedge.
■ Ask the students to identify the simple machines
at work in the transparency. (They are the
inclined plane, lever, and wheel and axle; perhaps
a pulley is used on the rear sliding door.)
■ Have the students identify other machines in their
daily lives, such as bicycles, garage doors, skateboards, etc.
■
Content Background
■
■
■
■
■
The wedge was probably the earliest tool, edged
rocks being used by prehistoric people to split
bones.
A lever-balance device was probably used in Egypt
about 5000 B.C. The inclined plane may date to
about the same time.
The wheel has been dated to Sumeria, around
3500 B.C. The spoked wheel and axle date to Asia
Minor, around 2000 B.C.
In the third century B.C., Archimedes supposedly
pulled a boat from the water using a compound
pulley.
The Greeks may have been the first to use the
screw, using it to press clothes in the second century B.C. One hundred years later, the screw was
being used to press oil and wine.
Answers to Student Worksheet
1. The ramp and the dolly are helping the mover get
the boxes out of the truck.
2. There are wheels on the truck and wheels on the
dolly.
3. Answers will vary. Students will probably mention
the ramp and dolly. Other possibilities include
tools like hammers and screwdrivers for taking
large items apart. Encourage discussion of tools
that make work easier.
Teaching Transparency (page 45)
Newton’s Laws of Motion
Section 2
Transparency Teaching Tips
Use the transparency to introduce the concept that
motion occurs in predictable ways. Tell students
that in the 1600s, Isaac Newton developed three
laws of motion that helped to describe and predict
how everyday objects move.
■ Ask students to identify the forces at work in the
transparency. Remember to identify opposing
pairs of forces. For example, if students say the
hockey stick pushed the ball, they should also
indicate the ball exerted a force on the stick.
■
Motion, Forces, and Simple Machines
T13
Teacher Support & Planning
Teacher Guide & Answers (continued)
Reteaching Suggestion
Review with students the three laws of motion
and describe how the pictures on the transparency
illustrate these laws.
Extensions
Activity: In pairs, have students devise an activity
that demonstrates one of the laws of motion.
Students should conduct the activities for the class.
Challenge: Have students cut pictures from a
newspaper or magazine that show objects in
motion. Ask pairs of students to diagram and
explain the forces at work on the objects in two of
the pictures.
Answers To Student Worksheet
1. You can infer the forces are unbalanced.
2. a push from the hockey stick; friction with the
ground
3. The shopping cart will accelerate more because it
has less mass.
4. Newton’s third law of motion
5. the ground
6. The forces don’t cancel each other out because
they do not act on the same object. In this case,
one force acts on the wall, and the other acts on
the swimmer. The swimmer accelerates because
she is experiencing unbalanced forces.
■
Assessment Transparency (page 47)
Motion, Forces, and Simple Machines
Section 3
Answers
1. A. Students must realize that the railroad tracks
exert a force opposite in direction to the force
exerted by the train on the tracks.
2. G. To answer this question, students must
remember that friction is the force that resists
motion between two surfaces in contact; friction
acts opposite to the direction of motion. As it is
drawn, the train is moving forward, so the force of
friction must be indicated by arrow 2.
3. C. Forces indicated by arrows 2 and 4 are pointing
in opposite directions, so, if they are the same
size, they are balanced. Balanced forces do not
cause a change in an object’s motion.
Choice A: No, accelerating the train is a change in
motion.
Choice B: No, decelerating the train is also a
change in motion.
Choice C: Yes, the train will keep constant motion
on a straight track.
Choice D: No, this is similar to decelerating.
Test-Taking Tip
Remind students to read each question carefully to
be sure they understand what is being asked.
T14 Motion, Forces, and Simple Machines
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Teacher Support & Planning
Teacher Guide & Answers (continued)

Documentos relacionados