Physics Midterm Review #1

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Chapter 2 – Linear Motion
1. True/False The rate at which velocity
changes with time is called acceleration.
2. True/False A unit of acceleration is
meters per second.
3. True/False When a car rounds a corner
at a constant speed, its acceleration is
zero.
4. True/False A ball is thrown in the air.
At the highest point, the ball has a zero
velocity and zero acceleration.
5. True/False As a ball falls freely, the
distance it falls each second is the same.
6. Speed is
a. A measure of how fast
something is moving
b. The distance covered per unit
time.
c. Always measured in terms of a
unit of distance divided by a
unit of time.
d. All of the above
7. One possible unit of speed is
a. Miles per hour
b. Kilometers per hour
c. Light years per century
d. All of the above
8. When you look at the speedometer in a
moving car, you can see the car’s
a. Instantaneous speed
b. Average speed
c. Instantaneous acceleration
d. Average acceleration
e. Average distance traveled
9. Suppose you take a trip that covers 240
km and takes 4 hours. Your average
speed is
a. 480 km/h
b. 240 km/h
c. 120 km/h
d. 60 km/h
10. Acceleration is defined as the CHANGE
in
a. Position divided by the time
interval
b. Velocity divided by the time
interval
c. Time it takes to move from one
speed to another speed
d. Time it takes to move from one
place to another place
11. Suppose you are in a car that is going
around a curve. The speedometer reads a
constant 30 miles per hour. Which of the
following is NOT true?
a. You and the car are accelerating
b. Your speed is constant
c. Your velocity is constant
d. Your acceleration is constant
12. Suppose a car is moving in a straight
line and steadily increases its speed. It
moves from 35 km/f to 40 km/h the first
second and from 40 km/h to 45 km/h the
next second. What is the car’s
acceleration?
a. 5 km/h/s
b. 10 km/h/s
c. 35 km/h/s
d. 40 km/h/s
13. A ball is thrown straight up. At the top
of its path its acceleration is
a. 0 m/s/s
b. About 5 m/s/s
c. About 10 m/s/s
d. About 20 m/s/s
14. What is the average speed of a cheetah
that runs 70 m in 2.5 seconds?
15. An apple falls from a tree and one-half
second later hits the ground. How fast is
it falling when it hits the ground?
Chapter 3 – Projectile Motion
1. True/False A quantity that has both
magnitude and direction is called a
scalar.
2. True/False A single vector can be
replaced by two vectors in the X and Y
directions. These X and Y vectors are
called the resultant of the original
vector.
3. True/False Wind velocity can be
represented as a vector quantity.
4. True/False The vertical component of
velocity for a projectile varies with time,
even with no air resistance.
5. True/False The horizontal component
of velocity for a projectile varies with
time, even with no air resistance.
6. A vector is a quantity that has
a. Magnitude and time
b. Magnitude and direction
c. Time and direction
7. When velocity is represented as a vector
a. The length of the arrow
represents the speed
b. The length of the arrow is
drawn to a suitable scale
c. The direction of the arrow
shows the direction of motion
d. All of the above
8. What is the minimum resultant possible
when adding a 3-unit vector to an 8-unit
vector?
a. 24
b. 11
c. 8
d. 5
9. What is the maximum resultant possible
when adding a 3-unit vector to an 8-unit
vector?
a. 24
b. 11
c. 8
d. 5
10. Which of the following would NOT be
considered a projectile?
a. A cannonball thrown through
the air
b. A cannonball rolling down a
slope
c. A cannonball thrown straight up
d. A cannonball rolling off the
edge of a table
11. The vertical component of a projectile’s
velocity is independent of
a. The horizontal component of its
velocity
b. The range of the projectile
c. Time
12. A ball is thrown into the air at some
angle between 10 degrees and 90
degrees. At the very top of the ball’s
path, its velocity is
a. Entirely vertical
b. Entirely horizontal
c. Both vertical and horizontal
d. There’s not enough information
given to determine
Chapter 4 – Newton’s First Law of
Motion – Inertia
1. True/False The amount of matter in an
object is called its weight.
2. True/False A unit of weight is the
kilogram.
3. True/False If a hockey puck slides on a
perfectly frictionless surface, it will
eventually slow down because of its
inertia.
4. True/False Inertia is the reluctance any
material object has to change in its state
of motion.
5. True/False The combination of all the
forces that act on an object is called the
net force.
6. Whirl a rock at the end of a string and it
follows a circular path. If the string
breaks, the tendency of the rock is to
a. Follow a spiral path
b. Continue to follow a circular
path
c. Follow a straight-line path
7. Galileo found that a ball rolling down
one inclined plane would roll how far up
another inclined plane?
a. To nearly twice the height as
where it originally started
b. To nearly the same height as
where it originally started
c. To nearly half its original height
d. To about one quarter its original
height
8. The law of inertia states that an object
a. At rest will remain at rest unless
acted on by an outside force
b. Will continue moving at the
same velocity unless an outside
force acts on it
c. Will continue moving in a
straight line unless an outside
force acts on it
d. All of the above
9. The law of inertia applies to
a. Moving objects
b. Objects at rest
c. Both moving and nonmoving
objects
10. After a cannonball is fired into
frictionless space, the amount of force
needed to keep it going equals
a. Twice the force with which it
was fired
b. The same amount of force with
which it was fired.
c. One half the force with which it
was fired
d. Zero, since no force is necessary
to keep it moving
11. Which has more mass, a kilogram of
feathers or a kilogram of iron?
a. The feathers
b. The iron
c. Neither. The masses are equal
12. A 10-N force and a 30-N force act on an
object in opposite directions. What is the
net force on the object?
a. 40 N
b. 30 N
c. 20 N
d. 10 N
13. On the surface of Jupiter the
acceleration due to gravity is about 3
times that on earth. How much would a
100 kg rock weigh on Jupiter?
14. List three differences between mass and
weight.
Chapter 5 – Newton’s Second Law of
Motion – Force and Acceleration
1. True/False Objects move only when a
force is exerted.
2. True/False The acceleration of an
object is inversely proportional to the
net force acting on it.
3. True/False The speed of an object
dropped in the air will continue to
increase without limit until it strikes the
ground.
4. The acceleration produced by a net force
on an object is
a. Directly proportional to the
magnitude of the net force.
b. In the same direction as the net
force.
c. Inversely proportional to the
mass of the object
d. All of the above
5. If the force acting on a cart doubles,
what happens to the cart’s acceleration?
a. It quadruples
b. It doubles
c. It halves
d. It quarters
6. A tennis ball and a solid steel ball the
same size are dropped at the same time.
Which ball has the greater force acting
on it?
a. The tennis ball
b. The steel ball
c. They both have the same force
acting on them.
7. A tennis ball and a solid steel ball the
same size are dropped at the same time.
In the absence of air resistance, which
ball has the greater acceleration?
a. The tennis ball
b. The steel ball
c. Nonsense! They both the same
acceleration
8. As he falls from a high-flying stationary
helicopter, Bronco’s velocity increases
and his acceleration
a. Decreases
b. Remains the same
c. Increases
9. You push with 30 N on a 3-kg block and
there are no opposing forces. What is
the block’s acceleration?
10. A 50-kg block of cement is pulled
upward (not sideways) with a force of
600 N. What is its acceleration?
Chapter 6 – Newton’s Third Law of
Motion – Action and Reaction
1. True/False Whenever one object exerts
a force on a second object, the second
object always exerts the same amount of
force back on the first object.
2. True/False A rocket is pushed forward
by gases that are forced out the back of
the ship.
3. True/False In order to make a cart
move forward, a horse must pull harder
on the cart than the cart pulls on the
horse.
4. True/False If a bicycle and a parked car
have a head-on collision, the force of
impact is greater on the bicycle.
5. True/False The earth and moon pull on
each other with equal amounts of force.
6. Whenever an object exerts a force on
another object, the second object exerts
a force of the same magnitude, but in the
opposite direction to that of the first
object.
a. Always true
b. Sometimes true
c. Always false
7. A high school student hits a nail with a
hammer. During the collision, there is a
force
a. On the hammer but not on the
nail.
b. On the nail but not on the
hammer
c. On the nail and also on the
hammer
8. A woman weighing 500 N sits on the
floor. She exerts a force on the floor of
a. 1000 N
b. 500 N
c. 250 N
d. 50 N
9. As a 500 N woman sits of the floor, the
floor exerts a force on her of
a. 1000 N
b. 500 N
c. 250 N
d. 50 N
10. Forces always occur
a. When velocities are constant
b. As single quantities
c. In pairs
d. In triplets
11. An unfortunate bug splatters against the
windshield of a moving car. Compared
to the force of the car on the bug, the
amount of force of the bug on the car is
a. Larger
b. Smaller
c. The same
12. An unfortunate bug spatters against the
windshield of a moving car. Compared
to the deceleration of the car, the
deceleration of the bug is
a. Larger
b. Smaller
c. The same
13. If a horse pulls on a wagon at rest, the
wagon pulls back equally as much on
the horse. Will the wagon be set into
motion?
a. No, because the forces cancel
each other out.
b. Yes, because there is a net force
acting on the wagon
c. Yes, because there is a time
delay between action and
reaction
d. Yes, because the horse’s pull on
the wagon is larger than the
wagon’s pull on the horse.
14. A 60-kg person on in-line skates pushes
against a wall with a force of 30 N and
recoils. What acceleration does that
person experience?
15. Apply Newton’s third law to a falling
boulder. Identify the action and reaction
forces.
3. Which of the following is NOT a unit of
rotational speed?
a. Revolutions per second
b. Rotations per second
c. Revolutions per minute
d. Meters per second
4. What is the direction of the force that
acts on clothes in the spin cycle of a
washing machine?
a. Outward
b. Inward
c. Up
d. Down
5. A tin can on the end of a string moves in
a circle because
a. Once the can starts moving, that
is its natural tendency
b. The can continually pulls on the
string
c. There is a force on the can
pulling it outward
d. The string continually pulls
inward on the can
6. If you whirl a tin can on the end of a
string and the string suddenly breaks,
the can will
a. Fly directly away from you
b. Fly directly towards you
c. Fly off, tangent to its circular
path
d. Spiral away from your hand
a. If a force is exerted on the earth, why
doesn’t it move?
Chapter 9 – Circular Motion
1. True/False Any force that causes an
object to move in a circular path is
called centripetal force.
2. True/False When you whirl a can on
the end of a string, the centripetal force
on the can is actually the pull of the
string on the can (tension).
7. A ladybug rests on the bottom of a tin
can that is being whirled in a horizontal
circle at the end of a string. What exerts
the force that holds this ladybug in a
circle?
a. Your hand
b. The string
c. The can
d. Gravity
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