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A boy is running to the east and jumps into a stationary boat in a lake. Once the boy lands in the boat, the boat moves to the east. Which best compares the initial momentum of the boy with the final momentum of the boy/boat system?

A
The initial momentum of the boy is equal to the boy/boat because the final velocity of the boat is less than the initial velocity of the boy.
B
The initial momentum of the boy is less than the boy/boat because the boy has less mass than the boat.
C
The initial momentum of the boy is zero because the velocity cancels with the mass of the boy.
D
The initial momentum of the boy is greater than the boy/boat because the boy has a greater velocity than the boat.
2
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An object with a mass of 20 kilograms has a net force of 80 cap n acting on it. What is the acceleration of the object?

A
4 the fraction with numerator m and denominator s squared
B
0 point 2 5 the fraction with numerator m and denominator s squared
C
100 the fraction with numerator m and denominator s squared
D
60 the fraction with numerator m and denominator s squared
3

If a 4 point 5 kilograms object is dropped from a height of 6 point 0 m , what will be its velocity when it is halfway toward the ground? (Use g is equal to 9 point 8 0 the fraction with numerator m and denominator s squared , and ignore air resistance.)

A
11 meters per second
B
16 meters per second
C
7.7 meters per second
D
29 meters per second
4

Suppose an object’s initial velocity is 10 meters per second and its final velocity is 4 meters per second Mass is constant. What can best be concluded about the object based on the work-energy theorem?

A
Work is negative, the object did work on the environment, and the energy of the system decreases.
B
Work is positive, the environment did work on the object, and the energy of the system increases.
C
Work is negative, the environment did work on the object, and the energy of the system decreases.
D
Work is positive, the object did work on the environment, and the energy of the system increases.
5

In the heat equation, what does Q represent?

A
mass of the substance
B
specific heat of the substance
C
heat required to raise the temperature
D
change in temperature
6

A cyclist rides at a constant speed of 4 point 5 m/s around a curve. If the centripetal acceleration is 29 m/s squared , what is the radius of the curve?

A
34 m
B
0 point 7 0 m
C
6 point 4 m
D
0 point 1 6 m
7

In the equation for centripetal force, which expression represents the centripetal acceleration of the object?

A
m over r
B
m v squared
C
the fraction with numerator m v squared and denominator r
D
the fraction with numerator v squared and denominator r
8

Which best illustrates projectile motion?

A
Image with description A pictorial diagram showing a hot air balloon in four different positions, each the same height from the ground and equally spaced.
B
Image with description A pictorial diagram with a rocket launched straight upward. The first three positions of the rocket are shown with equal spacing between them.
C
Image with description A pictorial diagram of a person hopping sideways at 5 different positions. The start and end positions are on the ground. The third image is the highest off the ground.
D
Image with description A pictorial diagram with a person swimming and position shown in equal time intervals and equally spaced.
9

A 150 g egg is dropped from 3 point 0 meters. The egg is moving at 4.4 meters per second right before it hits the ground. The egg comes to a stop in 0 point 0 7 2 seconds. What is the magnitude of force that the ground exerted on the egg?

A
13 cap n
B
0 point 6 6 cap n
C
9 point 2 cap n
D
180 cap n
11

Luke pulls a sled using a force of 65 cap n for a distance of 25 m across level ground. The rope Luke pulls forms an angle of 25 degrees with the ground. About how much work does Luke do on the sled?

A
250 J
B
1 comma 500 J
C
1 comma 600 J
D
690 J
12

What happens at the flat areas of a substance’s heating curve?

A
The average kinetic energy of the molecules increases, and the temperature remains the same.
B
Both the average kinetic energy of the molecules and the temperature decrease.
C
The average kinetic energy of the molecules decreases, and the temperature increases.
D
Both the average kinetic energy of the molecules and the temperature remain the same.
13

Two objects are interacting, but stay stationary. Which best describes what is happening to the action and reaction forces?

A
There are no forces acting on the objects.
B
The forces are equal and opposite each other.
C
Their forces are occurring at different times.
D
One object is exerting more force than the other.
14

Which describes the movement of a fluid during convection?

A
Warm fluid sinks and cool fluid rises.
B
Warm and cool fluids rise.
C
Warm and cool fluids sink.
D
Warm fluid rises and cool fluid sinks.
15

What did Johannes Kepler contribute to the study of planets?

A
He collected detailed data that led to the proposal of the heliocentric model.
B
He identified the first moons of Jupiter.
C
He provided mathematical support for the heliocentric model.
D
He formulated the universal law of gravitation.
17

The sun is made up mostly of

A
plasma material.
B
gas material.
C
solid material.
D
liquid material.
19

Which is an action that can cause an object to move or change its state of motion?

A
equilibrium
B
inertia
C
energy
D
force
20

A boat travels in a straight path that is 25 degrees west of north. Which describes the values of the west and north components of the boat’s displacement?

A
The west component is a positive number, and the north component is a negative number.
B
Both components are negative numbers.
C
The west component is a negative number, and the north component is a positive number.
D
Both components are positive numbers.
21

Which energy transformation occurs after a skydiver reaches terminal velocity?

A
Gravitational potential energy transforms into kinetic energy.
B
Gravitational potential energy transforms into thermal energy.
C
Kinetic energy transforms into thermal energy.
D
Kinetic energy transforms into gravitational potential energy.
22

Which formula can be used to find the centripetal acceleration of an orbiting object?

A
A sub c is equal to the fraction with numerator square root of v and denominator cap t
B
A sub c is equal to the fraction with numerator v squared and denominator r
C
A sub c is equal to the fraction with numerator v squared and denominator cap t
D
A sub c is equal to the fraction with numerator square root of v and denominator r
23

Sixty-three joules of heat are added to a closed system. The initial internal energy of the system is 58 J, and the final internal energy is 93 J. How much work is being done by the system?

A
151 J
B
88 J
C
30 J
D
28 J

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