As you read Chapter 6, which begins on page 136 of your textbook, answer the following questions.

Imagine . . . (p. 136)

1. What is the Vomit Comet?

2. In this chapter you will learn how

affects the of objects and how the

of apply to your life.

What Do You Think? (p. 137)

Answer these questions in your ScienceLog now. Then later, you’llhave a chance to revise your answers based on what you’ve learned.

Investigate! (p. 137)

3. What is the purpose of this activity?

Section 1: Gravity and Motion (p. 138)

4. Do you agree with what Aristotle might say, that the basketballwould land first, then the baseball, then the marble? Explain.

DIRECTED READING WORKSHEETS 41

Name _______________________________________________ Date ________________ Class______________

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DIRECTED READING WORKSHEET6

Forces in Motion

CHAPTERC

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All Objects Fall with the Same Acceleration (p. 138)

5. Did Galileo prove Aristotle wrong? Explain.

6. What does 9.8 m/s/s have to do with acceleration?

Air Resistance Slows Down Acceleration (p. 139)

7. Why does a crumpled piece of paper hit the ground before a flatsheet of paper?

8. Air resistance is affected by the

and of an object.

9. Air resistance matches the whenthe net force equals zero. (acceleration or force of gravity)

10. When a falling object stops , it has

reached velocity.

11. If there were no air resistance, hailstones woulda. hit the Earth at velocities near 350 m/s.b. float gently to the ground like snowflakes.c. melt before they hit the ground.d. behave exactly as they do now.

12. A sky diver experiences free fall. True or False? (Circle one.)

13. Free fall occurs because of high air resistance. True or False? (Circle one.)

Orbiting Objects Are in Free Fall (p. 141)

14. An astronaut is weightless in space. True or False? (Circle one.)

Name _______________________________________________ Date ________________ Class______________

42 HOLT SCIENCE AND TECHNOLOGY

Chapter 6, continued

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DIRECTED READING WORKSHEETS 43

15. The shuttle in Figure 7 follows the curve of the Earth’s surface as

it moves at a constant speed. At

the same time, it is in because ofthe Earth’s gravity.

16. Why don’t astronauts hit their head on the ceiling of the fallingshuttle?

17. Earth’s gravity provides a forcethat keeps the moon in orbit.

Projectile Motion and Gravity (p. 143)

18. The projectile motion of a leaping frog has two components—

and .

Mark each of the following statements True or False.

19. The components of projectile motion affect eachother.

20. Horizontal motion of an object is parallel to theground.

21. Ignoring air resistance, the horizontal velocity of athrown object never changes.

22. On Earth, gravity gives thrown objects their down-ward vertical motion.

23. If you shoot an arrow aimed directly at the bull’s-eye of your tar-get, where will the arrow hit your target? Why?

Review (p. 144)

Now that you’ve finished Section 1, review what you’ve learned byanswering the Review questions in your ScienceLog.

Chapter 6, continuedC

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As you read Chapter 6, which begins on page 136 of your textbook, answer the following questions.

Imagine . . . (p. 136)

1. What is the Vomit Comet?

The Vomit Comet is the KC-135 airplane, a plane designed to fly at high

speeds and different angles to simulate the effect of reduced gravity.

2. In this chapter you will learn how

affects the of objects and how the

of apply to your life.

What Do You Think? (p. 137)

Answer these questions in your ScienceLog now. Then later, you’llhave a chance to revise your answers based on what you’ve learned.

Investigate! (p. 137)

3. What is the purpose of this activity?

The purpose of this activity is to observe the effect of gravity on a

falling object.

Section 1: Gravity and Motion (p. 138)

4. Do you agree with what Aristotle might say, that the basketballwould land first, then the baseball, then the marble? Explain.

Accept any reasonable answer. Sample answer: No; I think that the

baseball would fall faster than the basketball because it has a higher

density.

motionlaws

motion

gravity

DIRECTED READING WORKSHEETS 41

Name _______________________________________________ Date ________________ Class______________

CH

AP

TER

6▼▼▼

DIRECTED READING WORKSHEET6

Forces in Motion

CHAPTERC

opyr

ight

© b

y H

olt,

Rin

ehar

t an

d W

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on.

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right

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ed.

All Objects Fall with the Same Acceleration (p. 138)

5. Did Galileo prove Aristotle wrong? Explain.

Yes; Galileo dropped two cannonballs of different masses from the

Leaning Tower of Pisa. The cannonballs hit at the same time, proving

that the mass of an object does not affect the rate at which it falls.

6. What does 9.8 m/s/s have to do with acceleration?

All objects accelerate toward Earth at a rate of 9.8 m/s/s. For every second

an object falls its downward velocity increases by 9.8 m/s.

Air Resistance Slows Down Acceleration (p. 139)

7. Why does a crumpled piece of paper hit the ground before a flatsheet of paper?

The flat piece of paper falls more slowly because of air resistance.

8. Air resistance is affected by the

and of an object.

9. Air resistance matches the whenthe net force equals zero. (acceleration or force of gravity)

10. When a falling object stops , it has

reached velocity.

11. If there were no air resistance, hailstones woulda. hit the Earth at velocities near 350 m/s.b. float gently to the ground like snowflakes.c. melt before they hit the ground.d. behave exactly as they do now.

12. A sky diver experiences free fall. True or False? (Circle one.)

13. Free fall occurs because of high air resistance. True or False? (Circle one.)

Orbiting Objects Are in Free Fall (p. 141)

14. An astronaut is weightless in space. True or False? (Circle one.)

terminal

accelerating

force of gravity

shape

size

Name _______________________________________________ Date ________________ Class______________

42 HOLT SCIENCE AND TECHNOLOGY

Chapter 6, continued

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by

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and

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Name _______________________________________________ Date ________________ Class______________

DIRECTED READING WORKSHEETS 43

15. The shuttle in Figure 7 follows the curve of the Earth’s surface as

it moves at a constant speed. At

the same time, it is in because ofthe Earth’s gravity.

16. Why don’t astronauts hit their head on the ceiling of the fallingshuttle?

Astronauts don’t hit their head on the falling shuttle because they are in

free fall just like the shuttle is.

17. Earth’s gravity provides a forcethat keeps the moon in orbit.

Projectile Motion and Gravity (p. 143)

18. The projectile motion of a leaping frog has two components—

and .

Mark each of the following statements True or False.

19. False The components of projectile motion affect eachother.

20. True Horizontal motion of an object is parallel to theground.

21. True Ignoring air resistance, the horizontal velocity of athrown object never changes.

22. True On Earth, gravity gives thrown objects their down-ward vertical motion.

23. If you shoot an arrow aimed directly at the bull’s-eye of your tar-get, where will the arrow hit your target? Why?

It will hit below the bull’s eye because the arrow accelerates downward as

it moves forward.

Review (p. 144)

Now that you’ve finished Section 1, review what you’ve learned byanswering the Review questions in your ScienceLog.

horizontalvertical

centripetal

free fall

forward

Chapter 6, continuedC

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