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Section 2: Newton’s Laws of Motion (p. 145)
1. In 1686, published Principia, a
work explaining laws to help people understand how forces relate to the
of objects.
Newton’s First Law of Motion (p. 145)
2. What is Newton’s first law?
3. An object in motion would keep moving forever if it never ran
into another object or an unbalanced force. True or False?(Circle one.)
4. is the unbalanced force that slowsdown sliding desks, rolling baseballs, and moving cars.
5. How does inertia explain why it would be so difficult to play softball with a bowling ball?
Name _______________________________________________ Date ________________ Class______________
44 HOLT SCIENCE AND TECHNOLOGY
Chapter 6, continued
Cop
yrig
ht ©
by
Hol
t, R
ineh
art
and
Win
ston
. A
ll rig
hts
rese
rved
.
Name _______________________________________________ Date ________________ Class______________
DIRECTED READING WORKSHEETS 45
Newton’s Second Law of Motion (p. 148)
6. What is Newton’s second law of motion?
7. Look at the Environmental Science Connection. A small car witha small engine cannot accelerate as well as a large car with a large
engine. True or False? (Circle one.)
8. An object’s acceleration decreases as the force on it increases.
True or False? (Circle one.)
9. Force equals times
.
10. The watermelon in Figure 16 has more
and than the apple, so the water-melon is harder to move than the apple.
Review (p. 149)
Now that you’ve finished the first part of Section 2, review whatyou’ve learned by answering the Review questions in yourScienceLog.
Newton’s Third Law of Motion (p. 150)
11. What is Newton’s third law of motion?
12. The phrase “equal and opposite” means that the action force and
the reaction force have the same
but act in opposite .
Chapter 6, continuedC
opyr
ight
© b
y H
olt,
Rin
ehar
t an
d W
inst
on.
All
right
s re
serv
ed.
CH
AP
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6▼▼▼
13. What action and reaction forces are present when you are sittingon a chair?
14. In a force pair, the reaction and action forces affect the same
object. True or False? (Circle one.)
15. When a ball falls off a ledge, gravity pulls the ball toward Earth
and also pulls Earth toward the ball. True or False? (Circle one.)
Momentum Is a Property of Moving Objects (p. 152)
16. Why does it take longer for a large truck to stop than it does fora compact car to stop, even though they are traveling at thesame velocity and the same braking force is applied?
17. Momentum depends on the and
of an object.
18. In Figure 19, during the collision, the momentum of the cue ball
a. is added to the total momentum.b. is transferred to the billiard ball.c. is transferred to the table holding the balls up.d. stays with the cue ball.
19. The law of conservation of momentum states that any time twoor more objects interact, they may exchange momentum, but the
total amount of momentum stays the same. True or False?(Circle one.)
Review (p. 153)
Now that you’ve finished Section 2, review what you’ve learned byanswering the Review questions in your ScienceLog.
Name _______________________________________________ Date ________________ Class______________
46 HOLT SCIENCE AND TECHNOLOGY
Chapter 6, continued
Cop
yrig
ht ©
by
Hol
t, R
ineh
art
and
Win
ston
. A
ll rig
hts
rese
rved
.
Section 2: Newton’s Laws of Motion (p. 145)
1. In 1686, published Principia, a
work explaining laws to help people understand how forces relate to the
of objects.
Newton’s First Law of Motion (p. 145)
2. What is Newton’s first law?
An object at rest remains at rest and an object in motion remains in
motion at a constant speed and in a straight line unless acted on by
an unbalanced force.
3. An object in motion would keep moving forever if it never ran
into another object or an unbalanced force. True or False?(Circle one.)
4. is the unbalanced force that slowsdown sliding desks, rolling baseballs, and moving cars.
5. How does inertia explain why it would be so difficult to play softball with a bowling ball?
The bowling ball has more mass than a softball, so it also has more inertia
than a softball. Having lots of inertia would make it difficult to change the
bowling ball’s direction once it is moving. After the bowling ball is pitched
toward you, it would be hard for you to bat it away with a bat.
Friction
motion
three
Sir Isaac Newton
Name _______________________________________________ Date ________________ Class______________
44 HOLT SCIENCE AND TECHNOLOGY
Chapter 6, continued
Cop
yrig
ht ©
by
Hol
t, R
ineh
art
and
Win
ston
. A
ll rig
hts
rese
rved
.
Name _______________________________________________ Date ________________ Class______________
DIRECTED READING WORKSHEETS 45
Newton’s Second Law of Motion (p. 148)
6. What is Newton’s second law of motion?
The acceleration of an object depends on the mass of the object and the
amount of force applied.
7. Look at the Environmental Science Connection. A small car witha small engine cannot accelerate as well as a large car with a large
engine. True or False? (Circle one.)
8. An object’s acceleration decreases as the force on it increases.
True or False? (Circle one.)
9. Force equals times
.
10. The watermelon in Figure 16 has more
and than the apple, so the water-melon is harder to move than the apple.
Review (p. 149)
Now that you’ve finished the first part of Section 2, review whatyou’ve learned by answering the Review questions in yourScienceLog.
Newton’s Third Law of Motion (p. 150)
11. What is Newton’s third law of motion?
Whenever one object exerts a force on a second object, the second object
exerts an equal and opposite force on the first. Or, all forces act in pairs.
12. The phrase “equal and opposite” means that the action force and
the reaction force have the same
but act in opposite .directions
size
inertia
mass
acceleration
mass
Chapter 6, continuedC
opyr
ight
© b
y H
olt,
Rin
ehar
t an
d W
inst
on.
All
right
s re
serv
ed.
CH
AP
TER
6▼▼▼
13. What action and reaction forces are present when you are sittingon a chair?
The action force is your weight pushing down on the chair. The reaction
force is the force exerted by the chair that pushes up on your body and is
equal to your weight.
14. In a force pair, the reaction and action forces affect the same
object. True or False? (Circle one.)
15. When a ball falls off a ledge, gravity pulls the ball toward Earth
and also pulls Earth toward the ball. True or False? (Circle one.)
Momentum Is a Property of Moving Objects (p. 152)
16. Why does it take longer for a large truck to stop than it does fora compact car to stop, even though they are traveling at thesame velocity and the same braking force is applied?
It takes the truck longer to stop because it has more momentum.
17. Momentum depends on the and
of an object.
18. In Figure 19, during the collision, the momentum of the cue ball
a. is added to the total momentum.b. is transferred to the billiard ball.c. is transferred to the table holding the balls up.d. stays with the cue ball.
19. The law of conservation of momentum states that any time twoor more objects interact, they may exchange momentum, but the
total amount of momentum stays the same. True or False?(Circle one.)
Review (p. 153)
Now that you’ve finished Section 2, review what you’ve learned byanswering the Review questions in your ScienceLog.
velocity
mass
Name _______________________________________________ Date ________________ Class______________
46 HOLT SCIENCE AND TECHNOLOGY
Chapter 6, continued
Cop
yrig
ht ©
by
Hol
t, R
ineh
art
and
Win
ston
. A
ll rig
hts
rese
rved
.