Download TITLE: Mechanical Equilibrium

TITLE: First Semester Practice Exam
Multiple Choice
1. When the net force is zero on a book at rest on a table, the book is in
a. static equilibrium.
b. dynamic equilibrium.
c. normal equilibrium.
d. rotational equilibrium.
ANS: A
Multiple Choice
2. When a 10-kg block is simultaneously pushed eastward with 20 N and westward with 15 N, the net
force on the block is
a. 35 N west.
b. 35 N east.
c. 5 N east.
d. 5 N west.
ANS: C
Multiple Choice
4. When you stand steadily on one foot on a bathroom scale with the other foot raised, the reading on
the scale equals
a. half your weight.
b. your weight.
c. somewhat more than your weight.
d. zero.
ANS: B
Multiple Choice
5. Jason's big brother gives him a piggyback ride. His brother weighs 650 N and Jason weighs 250 N.
The support force supplied by the floor must be
a. 250 N.
b. 400 N.
c. 900 N.
d. more than 900 N.
ANS: C
Multiple Choice
6. When a 10-N object is suspended at rest by a string, which of these does NOT occur?
a. The net force on the object is zero.
b. The tension in the string is zero.
c. The tension in the string is 10 N.
d. The object is in equilibrium.
ANS: B
Multiple Choice
7. When a 10-kg block is simultaneously pushed eastward with 20 N and westward with 20 N, the net
force on the block is
a. 20 N east.
b. 20 N west.
c. 40 N in either direction.
d. zero.
ANS: D
Multiple Choice
10. The force called tension is actually a force that tends to
a. stretch something.
b. compress something.
c. bend something.
d. break something
ANS: A
Multiple Choice
11. What is the maximum resultant possible when adding a 6-N force to 4-N force?
a. 8N
b. 10N
c. 2N
d. None of the above
ANS: B
Multiple Choice
12. Equilibrium occurs when
a. all the forces acting on an object are balanced.
b. the sum of the +x forces on an object equals the sum of the –x forces.
c. the net force on the object is zero.
d. the sum of the upward forces equals the sum of the downward forces.
e. all of the above
ANS: E
Multiple Choice
15. What is needed to describe a vector quantity?
a. only magnitude
b. only direction
c. both magnitude and direction
d. neither magnitude nor direction
ANS: C
Multiple Choice
16. A single vector can be replaced by two vectors in the x- and y-directions that are at right angles to each
other. These two x and y vectors are called the_______ of the original vector.
a. resultants
b. Components
c. Sum
ANS: B
Multiple Choice
17. A book is resting on a table. It has a weight of 15 N The support force of the table would be
a. Less than 15N
b. More than 15N
c. Equal to 15N
d. Zero Newtons
ANS: C
Multiple Choice
18. A object moving at a constant speed would
a. be in static equilibrium
b. be in dynamic equilibrium
c. have a net force greater than zero acting on it.
ANS: B
Multiple Choice
19. The forces acting on a suspended object at rest
a. Not balanced
b. Balanced
c. Are all equal to zero
ANS: B
Multiple Choice
20. The equilibrium rule can be expressed as
a. Forces are not balanced
b. Forces are greater than zero
c. Adding the forces as vectors yields a zero net force
d. Adding the forces yields a net force greater than zero.
ANS: C
Multiple Choice
1. The first scientist to be credited with the idea that Earth moves around the sun was
a. Aristotle.
b. Copernicus
c. Galileo.
d. Newton.
ANS: B
Multiple Choice
2. Mass is most closely related to
a. inertia.
b. weight
c. volume
d. location.
ANS: A
Multiple Choice
3. Weight is dependent on
a. gravity
b. location
c. mass
d. gravity, location, and mass.
ANS: D
Multiple Choice
5. Newton's first law is illustrated by
a. Aristotle's errors about motion.
b. Galileo's experiments on the Leaning Tower of Pisa
c. the downward motion of balls on Galileo's inclined planes
d. the equation ∑F = 0.
ANS: C
Multiple Choice
6. The weight of 1 kilogram of iron on Earth will weigh
a. less on the moon.
b. the same on the moon
c. more on the moon.
d. the same anywhere in the universe.
ANS: A
Multiple Choice
7. When standing in the aisle of a smoothly moving bus, you drop a coin from above your head. The
falling coin will land
a. at your feet
b. slightly in front of your feet.
c. slightly in back of your feet
d. at an unpredictable location.
ANS: A
Multiple Choice
8. The Earth moves about 30 km/s relative to the sun. When you jump upward in front of a wall, the
wall doesn't slam into you at 30 km/s. This is because the wall
a. has too little gravity to influence you
b. moves in an opposite direction to you.
c. and you are moving at the same speed, before, during, and after your jump
d. has negligible inertia compared with the sun.
ANS: C
Multiple Choice
9. Consider a ball resting in the middle of a cart. When you quickly jerk the cart forward, the
a. front of the cart hits the ball
b. back of the cart hits the ball
c. ball remains in the middle as the cart moves forward
d. ball's direction depends on how quickly the cart is pulled.
ANS: B
Multiple Choice
10. If you swing string with a stone attached overhead in a horizontal circle, and the string breaks, the
tendency of the stone is to follow a
a. curved path
b. straight-line path
c. spiral path
d. vertical path.
ANS: B
Multiple Choice
11. Which has the greatest mass?
a. 1 kilogram of iron
b. 2 kilograms of pennies
c. 3 kilograms of water
d. 4 kilograms of feathers
ANS: D
Multiple Choice
12. Galileo's conclusions about motion helped advance science because they were based on
a. philosophical discussions rather than experiments
b. experiments rather than philosophical discussions
c. nonmathematical thinking
d.public opinion
ANS: B
Multiple Choice
13. The concept of inertia mostly involves
a. mass
b. weight
c. volume
d. density.
ANS: A
Multiple Choice
14. Friction
a. comes from microscopic bumps that act as obstructions to the object's motion.
b. is the name given to the force acting between surfaces sliding past one another.
c. acts in a direction that opposes the motion of an object.
d. all of the above
e. none of the above
ANS: D
Multiple Choice
15. How much does a 5 kg bag of potatoes weigh?
a. 5 N
b. 25 N
c. 50 N
d. 100 N
ANS: C
Multiple Choice
1.
Speed is
a.
a measure of how fast something is moving.
b.
always measured in terms of a unit of distance divided by a unit of time.
c.
the distance covered per unit time.
d.
all of the above.
e.
none of the above.
ANS: D
Multiple Choice
2.
One possible unit of speed is
a.
b.
c.
d.
e.
ANS: D
miles per hour.
light years per century.
kilometers per hour.
all of the above.
none of the above.
Multiple Choice
3.
When you look at the speedometer in a moving car, you can see the car's
a.
average distance traveled.
b.
instantaneous acceleration.
c.
average speed.
d.
instantaneous speed.
e.
average acceleration.
ANS: D
Multiple Choice
4.
Acceleration is defined as the CHANGE in
a.
time it takes to move from one place to another place.
b.
velocity of an object.
c.
distance divided by the time interval.
d.
velocity divided by the time interval.
e.
time it takes to move from one speed to another speed.
ANS: D
Multiple Choice
5.
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 acceleration is constantly changing.
c.
Your velocity is constant.
d.
Your direction is constantly changing.
e.
Your speed is constant.
ANS: C
Multiple Choice
6.
A train travels 6 meters in the first second of travel, 6 meters again during the second second of travel, and 6
meters again during the third second. Its acceleration is
a.
0 m/s2.
b.
6 m/s2.
c.
12 m/s2.
d.
18 m/s2.
e.
none of the above
ANS: A
Multiple Choice
7.
A car starts from rest and after 7 seconds it is moving at 42 m/s. What is the car’s average acceleration?
a.
0.17 m/s2
b.
1.67 m/s2
c.
6 m/s2
d.
7 m/s2
e.
none of the above
ANS: C
Multiple Choice
8.
As an object falls freely in a vacuum, its
a.
velocity increases.
b.
acceleration increases.
c.
both A and B.
d.
none of the above.
ANS: A
Multiple Choice
9.
In the absence of air resistance, objects fall at constant
a.
speed.
b.
velocity.
c.
acceleration.
d.
distances each successive second.
e.
all of the above
ANS: C
Multiple Choice
10.
A ball is thrown upwards and caught when it comes back down. In the absence of air resistance, the speed of the
ball when caught would be
a.
less than the speed it had when thrown upwards.
b.
more than the speed it had when thrown upwards.
c.
the same as the speed it had when thrown upwards.
ANS: C
Multiple Choice
11.
Suppose an object is in free fall. Each second the object falls
a.
the same distance as in the second before.
b.
a larger distance than in the second before.
c.
with the same instantaneous speed.
d.
with the same average speed.
e.
none of the above
ANS: B
Multiple Choice
12.
If you drop a feather and a coin at the same time in a tube filled with air, which will reach the bottom of the tube
first?
a.
The feather
b.
Neither—they will both reach the bottom at the same time.
c.
The coin
ANS: B
Multiple Choice
13.
A ball tossed vertically upward rises, reaches its highest point, and then falls back to its starting point. During this
time the acceleration of the ball is always
a.
in the direction of motion.
b.
opposite its velocity.
c.
directed downward.
d.
directed upward.
ANS: C
Multiple Choice
14.
When a basketball player jumps to make a shot, once the feet are off the floor, the jumper's acceleration
a.
varies with body orientation.
b.
depends on launch speed.
c.
is usually greater for taller players (but not always).
d.
depends on all the above.
e.
is g; no more, no less.
ANS: E
Multiple Choice
16.
a.
b.
c.
d.
ANS: C
Acceleration is defined as
the rate at which distance is covered
the rate at which an object freely falls from rest
the rate at which velocity itself changes
the distance an object has fallen
Multiple Choice
17.
Suppose you take a trip that covers 180 km and takes 3 hours to make. Your average speed is
a.
30 km/h.
b.
60 km/h.
c.
180 km/h.
d.
360 km/h.
e.
540 km/h.
ANS: B
Multiple Choice
18.
Suppose a car is moving in a straight line and steadily increases its speed. It moves from 35 km/h 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
e.
45 km/h•s
ANS: A
Multiple Choice
19.
A ball is thrown straight up. At the top of its path its instantaneous speed is
a.
0 m/s.
b.
about 5 m/s.
c.
about 10 m/s.
d.
about 20 m/s.
e.
about 50 m/s.
ANS: A
Multiple Choice
20.
A ball is thrown straight up. At the top of its path its acceleration is
a.
0 m/s2.
b.
about 5 m/s2.
c.
about 10 m/s2.
d.
about 20 m/s2.
e.
about 50 m/s2.
ANS: C
Multiple Choice
21.
When something falls to the ground, it accelerates. This acceleration is called the acceleration due to gravity and is
symbolized by the letter g. What is the value of g on Earth's surface?
a.
0 m/s2
b.
about 5 m/s2
c.
about 10 m/s2
d.
about 20 m/s2
e.
about 50 m/s2
ANS: C
Multiple Choice
22.
A car accelerates at 2 m/s2. Assuming the car starts from rest, how much time does it need to accelerate to a speed
of 20 m/s?
a.
2 seconds
b.
c.
d.
e.
ANS: B
10 seconds
20 seconds
40 seconds
none of the above
Multiple Choice
23.
If a freely falling object were somehow equipped with a speedometer, its speed reading would increase each
second by
a.
about 5 m/s.
b.
about 10 m/s.
c.
about 15 m/s.
d.
a variable amount.
e.
a rate that depends on its initial speed.
ANS: B
Multiple Choice
24.
If a ball were equipped with a speedometer and allowed to fall freely on a planet where the acceleration due to
gravity is 23 m/s2, the reading on the speedometer would increase each second by
a.
a rate that depends on its initial speed.
b.
10 m/s.
c.
12 m/s.
d.
23 m/s.
e.
46 m/s.
ANS: D
Multiple Choice
25.
A freely falling object starts from rest. After falling for 6 seconds, it will have a speed of about
a.
6 m/s.
b.
30 m/s.
c.
60 m/s.
d.
300 m/s.
e.
more than 300 m/s.
ANS: C
Multiple Choice
28.
If a projectile is fired straight up at a speed of 30 m/s, the total time to return to its starting point is about
a.
3 seconds.
b.
6 seconds.
c.
30 seconds.
d.
60 seconds.
e.
not enough information to estimate.
ANS: B
Multiple Choice
1.
A vector is a quantity that has
a.
magnitude and time.
b.
time and direction.
c.
magnitude and direction.
ANS: C
Multiple Choice
2.
A scalar is a quantity that has
a.
direction.
b.
magnitude.
c.
time.
d.
color.
ANS: B
Multiple Choice
3.
When representing velocity as a vector,
a.
the direction of the arrow shows the direction of motion.
b.
the length of the arrow represents the speed.
c.
the length of the arrow is drawn to a suitable scale.
d.
all of the above
e.
none of the above
ANS: D
Multiple Choice
4.
In order to find the components of a vector, you should
a.
draw the vector with correct magnitude and orientation.
b.
measure the sides of the rectangle.
c.
draw a triangle so that the vector is the diagonal ( HYPOTENUSE).
d.
all of the above
ANS: D
Multiple Choice
5.
Which of the following would NOT be considered a projectile?
a.
A cannonball thrown straight up
b.
A cannonball rolling down a slope
c.
A cannonball rolling off the edge of a table
d.
A cannonball thrown through the air
e.
All of the above are projectiles.
ANS: B
Multiple Choice
6.
The horizontal component of a projectile's velocity is independent of
a.
the range of the projectile.
b.
time.
c.
the vertical component of its velocity.
ANS: C
Multiple Choice
7.
Assuming the projectile is launched on the earth, in the absence of air friction, the vertical
component of a projectile's velocity doesn't change as the projectile moves.
a.
Always false
b.
Always true
c.
Sometimes true
ANS: A
Multiple Choice
8.
In the absence of air friction, the horizontal component of a projectile's velocity doesn't change
as the projectile moves.
a.
Sometimes true
b.
Always true
c.
Always false
ANS: B
Multiple Choice
9.
At the instant a ball is thrown horizontally with a large force, an identical ball is dropped from
the same height. Which ball hits the ground first?
a.
Neither. They both hit the ground at the same time.
b.
The dropped ball
c.
The horizontally thrown ball
ANS: A
Multiple Choice
10.
A ball is thrown into the air at some angle. At the very top of the ball's path, its velocity is
a.
entirely vertical.
b.
There's not enough information given to determine.
c.
both vertical and horizontal.
d.
entirely horizontal.
ANS: D
Multiple Choice
11.
In the absence of air resistance, the angle at which a thrown ball will go the farthest is
a.
15 degrees.
b.
30 degrees.
c.
45 degrees.
d.
60 degrees.
e.
75 degrees.
ANS: C
Multiple Choice
12.
A ball thrown in the air will never go as far as physics ideally would predict because
a.
one can never throw the ball fast enough.
b.
gravity is acting.
c.
air friction slows the ball.
d.
ideally the ball would never land.
e.
all of the above
ANS: C
Multiple Choice
13.
At what part of a path does a projectile have minimum speed?
a.
When it returns to the ground
b.
Halfway to the top
c.
At the top of its path
d.
When it is thrown
e.
There's not enough information to say.
ANS: C
Multiple Choice
14.
A cannonball is launched from the ground at an angle of 30 degrees above the horizontal and a
speed of 30 m/s. Ideally (no air resistance) the ball will land on the ground with a speed of
a.
0 m/s.
b.
20 m/s.
c.
30 m/s.
d.
40 m/s.
e.
There is not enough information to say.
ANS: C
Multiple Choice
15.
A projectile launched horizontally hits the ground in 0.8 seconds. If it had been launched with a
much higher speed in the same direction, it would have hit the ground (neglecting Earth's curvature
and air resistance) in
a.
more than 0.8 s.
b.
0.8 s.
c.
less than 0.8 s.
ANS: B
Multiple Choice
16.
A projectile is fired horizontally in a vacuum. The projectile maintains its horizontal
component of speed because it
a.
has no vertical component of speed to begin with.
b.
is not acted on by any forces.
c.
the net force acting on it is zero.
d.
is not acted on by any horizontal forces.
e.
none of the above
ANS: D
Multiple Choice
17.
An object is dropped and falls freely to the ground with an acceleration of g. If it is thrown
upward at an angle instead, its acceleration would be
a.
0.
b.
larger than g.
c.
g upward.
d.
g downward.
e.
none of the above
ANS: D
Multiple Choice
18.
A baseball is hurled into the air at an angle of 30 degrees above the horizontal and lands on a
target that is at the same level as that where the baseball started. The baseball will also land on the
target if it is thrown at an angle of
a.
20 degrees.
b.
40 degrees.
c.
50 degrees.
d.
60 degrees.
e.
none of the above
ANS: D
Multiple Choice
19.
A cannonball is launched horizontally from a tower. If the cannon has a barrel velocity of 60
m/s, where will the cannonball be 1 second later? (Neglect air resistance.)
a.
6 m downrange
b.
30 m downrange
c.
60 m downrange
d.
300 m downrange
e.
none of the above
ANS: D
Multiple Choice
20.
After a rock that is thrown straight up reaches the top of its path and is starting to fall back
down, its acceleration is (neglecting air resistance)
a.
less than when it was at the top of its path.
b.
greater than when it was at the top of its path.
c.
the same as when it was at the top of its path.
ANS: C
Multiple Choice
21.
Which best approximates the resultant of a pair of 6-unit vectors at right angles to each other?
a.
0 units.
b.
6 units.
c.
8 units.
d.
12 units.
ANS: C
Multiple Choice
22.
What is the resultant of a 3-unit vector and 4-unit vector at right angles to each other?
a.
1 unit.
b.
5 units.
c.
7 units.
d.
none of the above
ANS: B
Multiple Choice
23.
Suppose a small plane can fly at 170 km/h relative to the surrounding air. Suppose also that
there is a 60 km/h tailwind. How fast does the plane's shadow move across the ground?
a.
5 km/h
b.
60 km/h
c.
110 km/h
d.
170 km/h
e.
230 km/h
ANS: E
Multiple Choice
24.
In the absence of air resistance, at what other angle will a thrown ball go the same distance as
one thrown at an angle of 75 degrees?
a.
15 degrees.
b.
65 degrees.
c.
70 degrees.
d.
80 degrees.
e.
90 degrees.
ANS: A
Multiple Choice
25.
A ball is thrown straight upward at 10 m/s. Ideally (no air resistance), the ball will return to the
thrower's hand with a speed of
a.
0 m/s.
b.
5 m/s.
c.
10 m/s.
d.
20 m/s.
e.
There is not enough information to say.
ANS: C
Multiple Choice
1. Anna and Marie go sky diving. Anna is heavier than Marie, but both use the same size parachute.
Anna has a greater terminal speed compared with Marie because
a. gravity acts on her more.
b. she has to fall faster for air resistance to match her weight.
c. she has greater air resistance.
d. she has weaker terminal velocity.
ANS: B
Multiple Choice
2.
A tennis ball filled with lead and a regular tennis ball are dropped from the top of a tall building
at the same time. The ball that experiences the greater amount of air resistance FORCE is the
a.
lead-filled tennis ball.
b.
regular tennis ball.
c.
Both the lead-filled and regular tennis balls experience the same amount of air resistance.
d.
no way to say with the given information
ANS: A
Multiple Choice
3. A tennis ball filled with lead and a regular tennis ball are dropped from the top of a tall building at
the same time. Both encounter air resistance. Which reaches the ground first?
a. the lead-filled tennis ball
b. the regular tennis ball
c. Both the lead-filled and regular tennis balls reach the ground at the same time.
d. no way to say with the given information
ANS: A
Multiple Choice
4. When you stand on one foot instead of two, the force you exert on the ground is
a. half.
b. the same.
c. double.
d. quadruple.
ANS: B
Multiple Choice
5. A math book and a physics book are tied together with a length of string. With the string taut, one
book is pushed off the edge of a table. As it falls, the other book is dragged horizontally across the
table surface. With no friction, acceleration of the books is
a. 2 m/s/s
b. 10 m/s/s
c. a value between zero and 10 m/s/s.
d. a value that could be greater than 10 m/s/s.
ANS: C
Multiple Choice
6. An object will accelerate when
a. it is unbalanced.
b. it is pushed or pulled with a net force.
c. its mass increases.
d. its mass decreases.
ANS: B
Multiple Choice
7. When a net force acts on an object, its acceleration depends on the object's
a. initial speed.
b. volume.
c. weight.
d. mass.
ANS: D
Multiple Choice
8. Use Newton's second law to answer this question: The acceleration of a vertically thrown ball at the
top of its path is
a. zero.
b. 10 m/s2.
c. between zero and 10 m/s2.
d. dependent on the initial speed of the ball.
ANS: B
Multiple Choice
9. When you drop a ball it accelerates downward at 10 m/s2. If you instead throw it downward, then its
acceleration immediately after leaving your hand, assuming no air resistance, is
a. 10 m/s2.
b. more than 10 m/s2.
c. less than 10 m/s2.
d. cannot say, unless the speed of throw is known
ANS: A
Multiple Choice
10. If a 10-kg rock and 5-kg rock are dropped from the same height, at the same time, and in the
absence of air resistance, then they will fall
a. at different speeds.
b. at different accelerations.
c. with the same acceleration.
d. with net forces of zero.
ANS: C
Multiple Choice
11. The type of force that causes acceleration.
a. balanced
b. negligible
c. zero
d. unbalanced
ANS: D
Multiple Choice
12. The combination of forces acting on an object is known as the ______
force.
a. positive
b. net
c. component
d. none of the above
ANS: B
Multiple Choice
13. The acceleration of an object is directly proportional to the net force acting on it. This means
that, as the net force acting on the object increases, the acceleration of the object _________.
a. stays the same
b. increases
c. decreases
ANS: B
Multiple Choice
14. Which statement about force and acceleration that is true.
a. Balanced forces cause constant accelerations.
b. The forces acting on an object at rest are unbalanced.
c. A net force acting on an object causes acceleration.
d. Force is not required for an object to accelerate.
ANS: C
Multiple Choice
15. Which of the following shows how mass and acceleration are related.
a. acceleration ~ mass
b. acceleration ~ 1/mass
c. acceleration ~ mass squared
d. acceleration ~ ½ mass
ANS: B
Multiple Choice
16. Which statement related to Newton’s second law that is true.
a. Acceleration is directly proportional to the balanced force.
b. The direction of acceleration is the same as the net force.
c. Acceleration is inversely proportional to mass.
d. Net force and mass are always equal.
ANS: C
Multiple Choice
17. A100-N force is used to accelerate a large push cart across the floor. What force required to
accelerate the push cart twice as fast.
a. 50 N
b. 100 N
c. 150 N
d. 200 N
ANS: D
Multiple Choice
18. An object accelerates when a net force is applied to it. Which of the following describing the
conditions that would double the object’s acceleration.
a. doubling the mass
b. halving the force
c. doubling the mass and halving the force
d. halving the mass
ANS: D
Multiple Choice
19. Which of the following best describes pressure.
a. the applied force that acts on an object
b. force per unit of area
c. the area to which a force is applied
d. force times surface area
ANS: B
Multiple Choice
20. Which of the following describes the unit of pressure known as a pascal?
a. newtons × area
b. newton per meter
c. newtons per square meter
d. square meters per second
ANS: C
Multiple Choice
21. Which statement about freely falling objects is the most correct?
a. They all fall with the same acceleration.
b. The net force acting on them is their weight.
c. Their weight-to-mass ratios are always the same.
d. Their acceleration is g, the acceleration due to gravity.
e. All of the above.
ANS: E
Multiple Choice
22. Which of the following best describes the forces that are in balance when an object reaches
its terminal speed.
a. mass and air resistance
b. air resistance and friction
c. friction and mass
d. weight and air resistance
ANS: D
Multiple Choice
1. 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.
Sometimes true
b.
Always true
c.
Always false
ANS: B
Multiple Choice
2. Fred hits a nail with a hammer. During the collision, there is a force
a.
on the nail but not on the hammer.
b.
on the nail and also on the hammer.
c.
on the hammer but not on the nail.
ANS: B
Multiple Choice
3. Forces always occur
a.
as single quantities.
b.
by themselves.
c.
in pairs.
d.
in triplets.
ANS: C
Multiple Choice
4. Barney shoots an arrow. Consider the action force to be the bowstring against the arrow. The
reaction to this force is the
a.
arrow's push against the bowstring.
b.
weight of the arrow.
c.
friction of the ground against the archer's feet.
d.
air resistance against the bow.
e.
grip of the archer's hand on the bow.
ANS: A
Multiple Choice
5. Diane catches a ball. Consider the action force to be the impact of the ball against the player's glove.
What is the reaction to this force?
a.
The muscular effort in the player's arms
b.
The force the glove exerts on the ball
c.
Friction of the ground against the player's shoes
d.
The player's grip on the glove
e.
none of the above
ANS: B
Multiple Choice
6. Diane hits a ball with a bat. The action force is the impact of the bat against the ball. What is the
reaction to this force?
a.
The force of the ball against the bat
b.
The weight of the ball
c.
Air resistance on the ball
d.
The grip of the player's hand against the bat
e.
none of the above
ANS: A
Multiple Choice
7. As a book falls, the action force is the pull of Earth's mass on the book. What is the reaction to this
force?
a.
The pull of the book's mass on Earth
b.
The acceleration of the book
c.
Nonexistent in this case
d.
Air resistance acting against the book
e.
none of the above
ANS: A
Multiple Choice
8. Josey is attracted towards the center of Earth by a 440-N gravitational force. The force with which
Earth is attracted toward Josey is
a.
440 N.
b.
very very small.
c.
very very large.
ANS: A
Multiple Choice
9. An unfortunate bug splatters against the windshield of a moving car. Compared to the force of the
car on the bug, the force of the bug on the car is
a.
larger.
b.
the same.
c.
smaller.
d.
Need more information to say
ANS: B
Multiple Choice
10. An unfortunate bug splatters against the windshield of a moving car. Compared to the deceleration
of the car, the deceleration of the bug is
a.
larger.
b.
the same.
c.
smaller.
ANS: A
Multiple Choice
11. If a horse pulls on a wagon at rest, the wagon pulls back equally on the horse. Can the wagon be set
into motion?
a.
Yes, because there is a net force acting on the wagon.
b.
Yes, because there is a time delay between action and reaction.
c.
No, because the forces cancel each other.
d.
Yes, because the horse's pull on the wagon is larger than the wagon's pull on the horse.
ANS: A
Multiple Choice
12. A large bus and a small car traveling at the same speed have a head-on collision. The vehicle to
undergo the greater change in velocity will be
a.
the small car.
b.
the large bus.
c.
neither—both are the same
ANS: A
Multiple Choice
13. According to Newton's third law, if you push gently on something, it will push
a.
gently on something else.
b.
on you only if you aren't moving.
c.
gently on you.
d.
on something only under the right conditions.
ANS: C
Multiple Choice
14. Earth pulls on the moon, and similarly the moon pulls on Earth. This is evidence that the
a.
Earth and moon are simply pulling on each other.
b.
Earth's and moon's pulls comprise an action-reaction pair.
c.
both a and b
d.
neither a or b
ANS: C
Multiple Choice
15.
Neville Newton holds an apple in his hand. If action is Earth pulling on the apple, then reaction
is
a.
his hand providing a normal force on the apple.
b.
his hand pushing up on the apple.
c.
both A and B
d.
neither A nor B
ANS: D
Multiple Choice
16. Alicia the skydiver falls toward Earth. The attraction of Earth on Alicia pulls her down. The
reaction to this force is
a.
Alicia finally pushing against Earth's surface.
b.
Alicia pulling up on Earth.
c.
Earth's surface finally pushing against Alicia.
d.
neither A, B, nor C
ANS: B
Multiple Choice
17. A force is exerted on the tires of a car to accelerate the car along the road. The force is exerted by
the
a.
road.
b.
engine.
c.
tires.
d.
air.
ANS: A
Multiple Choice
18. A rocket is able to accelerate in the vacuum of space when it fires its engines. The force that
propels the rocket is the force
a.
of the rocket on the exhaust gases.
b.
of the exhaust gases on the rocket.
c.
neither A nor B
ANS: B
Multiple Choice
19. A karate chop delivers a blow of 2300 N to a board that breaks. The force that acts on the hand
during this feat
a.
is less than 2300 N.
b.
is 2300 N.
c.
is more than 2300 N.
d.
cannot be determined.
ANS: B
Multiple Choice
20. A woman weighing 550 N sits on the floor. She exerts a force on the floor of
a.
5.5 N.
b.
55 N.
c.
550 N.
d.
1100 N.
e.
5500 N.
ANS: C
Multiple Choice
21. As a 600-N woman sits on the floor, the floor exerts a force on her of
a.
6 N.
b.
60 N.
c.
1200 N.
d.
600 N.
e.
6000 N.
ANS: D
Multiple Choice
22. Fred and Barney pull on a rope in a tug-of-war. Each pulls with 400 N of force. What is the tension
in the rope?
a.
0N
b.
400 N
c.
600 N
d.
800 N
e.
none of the above
ANS: B
Multiple Choice
24. Suppose you accidentally drive into a tree. Which of the following correctly describes the
interaction between your car and the tree?
a.
The car and the tree mutually exert equal forces in the same direction.
b.
The car and the tree mutually exert different forces in the same direction.
c.
The car and the tree mutually exert equal and opposite forces on each other.
d.
The car and the tree mutually exert different and opposite forces on each other.
ANS: C
Multiple Choice
25.
If your car runs out of gas, why can’t you push on the car’s dashboard from the inside to move
it?
a.
In order for the car to move, a force must be exerted by you on the car’s dashboard.
b.
In order for the car to move, a force must be exerted by the car’s dashboard on you.
c.
In order for the car to move, an outside force must be exerted on the car.
d.
In order for the car to move, a force must be exerted by the car on the ground.
ANS: C
Multiple Choice
26.
If you exert a force of 12,000 N on a 3,000 kg car and a 6,000 kg truck that are both originally
at rest, what will be the resulting accelerations of the objects?
a.
The car and the truck will both accelerate 12,000 m/s^2.
b.
The car will accelerate 1/4 m/s^2 and the truck will accelerate 1/2 m/s^2.
c.
The car will accelerate 4 m/s^2 and the truck will accelerate 2 m/s^2.
d.
The car will accelerate 36,000,000 m/s^2 and the truck will accelerate 72,000,000 m/s^2.
ANS: C