Student Name: ______________________________
Mrs. Lee – 8th Grade Physical Science
Period #: _______
Page 1
Chapter 10 Practice Test – Answer Key
______ c
1) How do you know an object is in motion?
a) It has inertia.
b) It has mass.
c) It is changing position
d) It has a reference point.
______ b
2) What is velocity?
a) speed
b) speed in a given direction
c) miles per hour
d) change in speed over time
______ b
3) Which is the best definition of acceleration?
a) change in velocity
b) change in reference point
c) increase in speed
d) decrease in speed
______ b
4) If an object starts out at rest and accelerates to 100 m / s, what is its initial speed?
a) –100 m / s
b) 0 m / s
c) 100 m / s
d) 32 m / s
______ b
5) Friction acts in a direction ______ to the direction of an object’s motion.
a) unrelated b) opposite
c) equal
d) perpendicular
______ b
6) Unless an object at rest is acted upon by a force, it stays at rest due to its ______.
a) matter
b) inertia
c) friction
d) gravity
______ a
7) A 10-kg ball is accelerated 500 m / s2 by a force of ______.
a) 5,000 N
b) 50 N
c) 500 N
d) 0.50 N
______ d
8) The momentum of a 1,500-kg car traveling at a velocity of 10 m / s is ______.
a) 15,000 N b) 15 m / s2 c) 150 N
d) 15,000 kg  m / s
______ a
9) A(n) ______ can cause an object’s motion to change.
a) unbalanced force b) balanced force
c) weight
d) inertia
______ d
10) The amount of matter in an object is called its ______.
a) weight
b) force
c) inertia
d) mass
______ c
11) Newton’s second law of motion states the relationship of mass, acceleration, and
force. It says that ______.
a) force equals mass divided by acceleration
b) force equals acceleration divided by mass
c) acceleration equals force divided by mass
d) every object attracts every other object in the universe
______ a
12) A(n) ______ causes objects to move in a circle.
a) centripetal force b) large weight
c) terminal velocity
______ d
d) acceleration
13) The unit of force, a Newton, is equal to ______.
a) the amount of mass in an object b) mass x velocity
c) kg  m / s
d) kg  m / s2
Ch 10 Practice Test Answer Key
1
Student Name: ______________________________
Mrs. Lee – 8th Grade Physical Science
Period #: _______
Page 2
Chapter 10 Practice Test – Answer Key
______ c
14) An object in free fall ______ until it reaches terminal velocity.
a) decreases in mass
b) slows down
c) accelerates
d) is unbalanced
______ b (force)
15) A push or a pull is a weight.
a) True
b) False
______ a
16) Friction between two objects that are not moving is static friction.
a) True
b) False
______ a
17) If gravity is the only force acting on an object, the object is in free fall.
a) True
b) False
______ b (mass)
18) The measure of the amount of matter in an object is the object’s force.
a) True
b) False
______ a
19) The momentum of an object depends on its mass and its velocity.
a) True
b) False
______ b (the same object) 20) Forces can be added together only if they are acting on different
objects.
a) True
b) False
______ a
21) According to Newton’s second law of motion, acceleration increases as force
increases, if mass stays the same.
a) True
b) False
______ a
22) The force due to gravity is stronger if two objects are closer.
a) True
b) False
______ b (gravity) 23) The force of friction acts between all objects in the universe.
a) True
b) False
______ a
24) A satellite in orbit around Earth is always falling toward Earth.
a) True
b) False
______ c
25) A force is described by ______.
a) its strength only
b) its direction only
______ c
______ b
26) What is the SI unit for force?
a) meter
b) meters per second
c) its strength and direction
c) Newton
27) When the forces acting on an object are balanced, the net force on the object is
______.
a) less than 0
b) exactly 0
c) more than 0
Ch 10 Practice Test Answer Key
2
Student Name: ______________________________
Mrs. Lee – 8th Grade Physical Science
Period #: _______
Page 3
Chapter 10 Practice Test – Answer Key
______ c
28) Friction acts ______.
a) in the same direction as motion
b) only on objects that are not in motion
c) in the opposite direction as motion
______ c
29) The friction on an object moving through water or air is ______.
a) rolling friction
b) sliding friction
c) fluid friction
______ a
30) The amount of gravity between two objects depends on their masses and the
______.
a) distance between them b) friction between them c) total velocity of the objects
______ c
31) The force of gravity on an object is known as its ______.
a) acceleration
b) mass
c) weight
______ a
32) Air resistance acts in what direction on a falling object?
a) upward
b) sideways c) downward
______ b
33) A(n) ______ causes an object’s motion to change.
a) inertia
b) unbalanced force c) balanced force
______ b
34) Newton’s third law says that for every action there is an equal and opposite
reaction. This law says that forces ______.
a) do not act on moving objects
b) comes in pairs
c) act only in the opposite direction of motion
______ a
35) Unbalanced forces change an object’s motion.
a) True
b) False
______ b
36) Friction causes moving objects to speed up.
a) True
b) False
______ b
37) The force of gravity between objects gets stronger as the objects move farther
apart.
a) True
b) False
______ a
38) The inertia of an object depends on its mass.
a) True
b) False
______ a
39) A centripetal force is the force that keeps a satellite in orbit.
a) True
b) False
Ch 10 Practice Test Answer Key
3
Student Name: ______________________________
Mrs. Lee – 8th Grade Physical Science
Period #: _______
Page 4
Chapter 10 Practice Test – Answer Key
The diagram below shows two balls. Use the diagram to answer the following 3 questions:
______ b
40) Calculating: The momentum of an object is its mass times its velocity. What is
the momentum of Ball A?
a) 1 kg  m /s
b) 2 kg  m /s
c) 3 kg  m / s
______ a
41) Calculating: What is the momentum of Ball B?
a) 0 kg  m /s
b) 1 kg  m / s
c) 10 kg  m / s
______ b
42) Applying Concepts: If Ball A hits Ball B, what will the total momentum of the
two balls be after the collision?
a) 1 kg  m / s
b) 2 kg  m / s
c) 3 kg  m / s
Use the graph below to answer the following 2 questions:
______ b
43) Interpreting Graphs: What is the object’s speed at 3 seconds?
a) 19.6 m / s
b) 29.4 m / s
c) 39.2 m / s
______ b
44) Applying Concepts: This graph shows an object in free fall. What is the only
force acting on this object?
a) air resistance
b) gravity
c) terminal velocity
Ch 10 Practice Test Answer Key
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