Matching
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Match each item with the correct statement below. a. | Newton’s first law of motion | f. | normal force | b. | unbalanced
forces | g. | Newton’s third
law of motion | c. | balanced forces | h. | force | d. | friction | i. | Newton’s second law of
motion | e. | net force |
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1.
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An object at rest or moving at a constant speed in a straight path will
continue to do so until a net force acts on it.
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2.
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An object acted upon by a net force will accelerate in the direction of the
force according to the equation acceleration =  .
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3.
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the outward force from a surface
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4.
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a push or a pull
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5.
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The net forces on an object are not zero.
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6.
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the total force felt by an object
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7.
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Forces always act in equal but opposite pairs.
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8.
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two or more forces whose effects cancel each other
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9.
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the rubbing force that acts against motion between two touching
surfaces
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Completion
Complete each
statement.
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Complete the following sentences using the terms listed below. Some terms may
not be used.
| accelerate | friction | velocity | static | | sliding | slipping | wheel | strength | | brake | inertia | terminal velocity | momentum | | | | |
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10.
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An object will ____________________ when the net force is not zero.
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11.
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____________________ will never speed up an object.
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12.
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The friction that prevents an object from moving when a force is applied is
____________________ friction.
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13.
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The friction that slows down an object that slides is ____________________
friction.
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14.
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A(n) ____________________ helps reduce sliding friction.
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15.
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Normal force is supplied by the ____________________ of the surface.
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16.
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The speed an object reaches when the force of gravity is balanced by the force
of air resistance is called ____________________.
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17.
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Earth has so much ____________________ that it hardly accelerates when you push
against the ground while walking.
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Choose the best of the three choices in parentheses.
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18.
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_____________________ (Static, Sliding, Rolling) friction keeps an object at
rest.
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19.
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_____________________ A force can (push, pull, either push or pull).
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20.
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The unbalanced force that stops almost everything is _____________________
(gravity, friction, momentum).
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21.
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An object will accelerate in the direction of the _____________________ (net
force, balanced forces, normal force).
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22.
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A net force acting on an object changes the object’s _____________________
(mass, size, momentum).
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23.
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Newton’s _____________________ (third, second, first) law of motion
describes the connection between an object supplying force and the object receiving the force.
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24.
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A force in the opposite direction to the motion of the object will cause the
object to _____________________ (speed up, slow down, turn).
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25.
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If an object is at rest, all forces acting on that object must be
_____________________ (unbalanced, balanced, normal).
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Short Answer
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26.
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Explain why it is easy to miss an action-reaction pair. Give an example.
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27.
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Why does friction never speed up an object?
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Multiple Choice
Identify the
choice that best completes the statement or answers the question.
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28.
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A(n) ____ is a push or a pull.
a. | newton | c. | force | b. | acceleration | d. | momentum |
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29.
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A ____ force is the total force felt by an object.
a. | sum | c. | strong | b. | net | d. | balanced |
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30.
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In order to be ____ forces, their effects must cancel each other out and not
cause a change in an object’s motion.
a. | balanced | c. | weak | b. | strong | d. | normal |
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31.
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If the forces acting on an object are unbalanced, the net force is NOT
____.
a. | normal | c. | weak | b. | strong | d. | zero |
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32.
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Newton’s first law of motion states that an object at rest or moving at a
constant speed in a(n) ____ will continue to do so until a net force acts on it.
a. | elliptical orbit | c. | state of acceleration | b. | straight
line | d. | curved
path |
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33.
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____ is the rubbing force that acts against motion between two touching
surfaces.
a. | Acceleration | c. | Momentum | b. | Normal force | d. | Friction |
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34.
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____ enables you to ride a bike without skidding and falling.
a. | Static friction | c. | Rolling friction | b. | Sliding friction | d. | Gravity |
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35.
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Applying the brakes uses ____ to slow a vehicle down.
a. | static friction | c. | rolling friction | b. | sliding friction | d. | gravity |
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36.
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In order to know how a force will affect an object, you must know the
____.
a. | normalcy | c. | direction | b. | weight | d. | gravity |
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37.
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Newton’s second law says that an object acted upon by a net force will
accelerate in the direction of the force according to the equation ____.
a. | Ft = mv2 – mv1 | c. | m1v1 =
m2v2 | b. | a =  | d. | v =
at |
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38.
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When you walk across a bridge, the ____ force of the bridge keeps it from
breaking.
a. | gravitational | c. | strong | b. | normal | d. | weak |
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39.
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The speed an object reaches when the force of gravity is balanced by the force
of air resistance is called ____.
a. | acceleration | c. | terminal velocity | b. | balanced velocity | d. | free fall |
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40.
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Newton’s third law can be stated as “For every action, there is a(n)
____ reaction.”
a. | equal but opposite | c. | stronger and opposite | b. | equal and
identical | d. | weaker and
opposite |
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41.
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You hit a wall with a stick. The equal but opposite reaction is ____.
a. | the wall pushes against you | c. | you push against the
stick | b. | the stick pushes against you | d. | the wall pushes against the
stick |
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42.
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The time for an action-reaction situation is ____.
a. | instantaneous | c. | no more than 1 second | b. | at least 5
seconds | d. | no more than 5
seconds |
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43.
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While static friction keeps an object at rest, ____ friction slows down an
object that slides.
a. | rolling | c. | static | b. | sliding | d. | none of these |
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44.
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The force of ____ exists between any two objects that have mass.
a. | gravity | c. | weight | b. | acceleration | d. | free fall |
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45.
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The gravitational force of any object near Earth’s surface is ____.
a. | unknown | c. | Newton’s first law | b. | friction | d. | 9.8m/s2 |
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46.
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If a net force acts at an angle to the direction an object is moving, the object
will follow a(n) ____ path.
a. | straight | c. | unknown | b. | curved | d. | straight
downward |
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Essay
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47.
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How could you use a roller skate, a sidewalk, and water to demonstrate how
rolling friction works?
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48.
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A marble is lying in the middle of the floor. Use Newton’s first law to
describe what will happen to the marble.
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49.
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A broom strikes the marble while you are sweeping. Use Newton’s second law
to describe what happens to the marble.
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50.
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Use Newton’s third law to describe what interaction there is between the
marble and the broom.
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51.
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What force must be applied to a 10-kg object to make it accelerate at
6m/s2?
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52.
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Why is terminal velocity an example of balanced forces?
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53.
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When you step out of a boat onto the dock, the boat moves. Why?
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54.
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Describe circular motion. Which of Newton’s laws helps you describe
circular motion?
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55.
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If action and reaction force pairs are equal and opposite, how can anything
move? Give an example of equal and opposite force pairs.
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