Download Name Class Date Skills Worksheet Directed Reading B Section

Name ______________________________ Class __________________ Date __________________
Skills Worksheet
Directed Reading B
Section: Newton’s Laws of Motion
1. In 1686, what did Sir Issac Newton explain with his three laws of motion?
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NEWTON’S FIRST LAW
2. What is Newton’s first law of motion?
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3. Which of Newton’s laws of motion describes the motion of an object that has a
net force of 0?
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4. What are two examples of objects at rest?
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5. How could an unbalanced force work on a chair at rest on the floor to make it
slide across the room?
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6. According to Newton’s first law of motion, what will happen to the motion of
objects moving with a certain velocity unless an unbalanced force acts on
them?
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7. If you were in a bumper car that stopped abruptly when it hit another car,
would you continue to move forward? Explain your answer.
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8. What unbalanced force acts to stop a desk that is sliding across a floor?
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Name ______________________________ Class __________________ Date __________________
Directed Reading B continued
9. What does friction do to the motion of objects?
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10. What is Newton’s first law sometimes called?
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11. What is the tendency of an object to resist being moved or, if the object is
moving, to resist a change in speed or direction until an outside force acts on
the object?
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12. Why is it easier to change the motion of an object with a small mass than it is
to change the motion of an object with a large mass?
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NEWTON’S SECOND LAW OF MOTION
13. What is Newton’s second law of motion?
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14. What happens to the acceleration of an object if the force on the object stays
the same as its mass decreases?
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15. What happens to the acceleration of an object if the force on the object
increases?
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16. What is the relationship between an object’s acceleration and the direction of
the force on the object?
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Name ______________________________ Class __________________ Date __________________
Directed Reading B continued
17. Why would a cart start moving faster if you gave it a hard push than if you
gave it a soft push?
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NEWTON’S THIRD LAW OF MOTION
18. What is Newton’s third law of motion?
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19. Explain why Newton’s third law can be stated as “all forces act in pairs.”
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20. What action and reaction forces are present when you are sitting on a chair?
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21. Since all forces act in pairs, what happens whenever a force is exerted?
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22. When a ball falls to Earth, why is it hard to see the effect of the reaction force
exerted by the ball on Earth?
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Name _____________________________ Class __________________ Date __________________
Skills Worksheet
Vocabulary and Section Summary B
Gravity: A Force of Attraction
VOCABULARY
After you finish reading the section, try this puzzle!
Oh no! Penny Punster’s computer mixed up her physical science dictionary with her
dictionary of puns. The computer paired the terms related to forces with her goofy
definitions, and it paired her pun-related terms with the real definitions. Help Penny
unscramble the mismatched pairs and get her dictionaries back in order.
a. gravity: dirty
English drink
b. static: pigpen
twitch
c. mass: spiked
medieval war club
d. weight: slowly
walk into the water
e. universal: a bad
salesperson
_____ 1. static: friction that disappears
object starts moving
_____ 2. grubby tea: force of attraction
objects due to mass
_____ 3. you never sell: applies to all
in the universe
_____ 4. wade: measure of the force of
on an object
_____ 5. mace: amount of matter in an
when an
between
objects
gravity
object
SECTION SUMMARY
Read the following section summary.
• Gravity is a force of attraction between objects that is due to their masses. Gravity can be
an unbalanced force that causes changes in velocity.
• Gravity holds the solar system together.
• The law of universal gravitation states that all objects attract each other through
gravitational force and that the magnitude of this force depends on the objects’ masses and
the distance between them.
• Mass is the amount of matter in an object. Weight is a measure of the
gravitational force on an object.
• Gravity is often balanced by elastic forces due to tension or compression.
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