Download 1) Two weightlifters, one 1.5 meters tall and one 2.0 meters tall, raise

6634 - 1 - Page 1
Name: ____________________________________________
1)
Two weightlifters, one 1.5 meters tall and one 2.0 meters tall, raise identical 50.-kilogram masses above their heads. Compared to the work done
by the weightlifter who is 1.5 meters tall, the work done by the weightlifter who is 2.0 meters tall is
A) the same
B) less
C) greater
2)
A student does 60. joules of work pushing a 3.0-kilogram box up the full length of a ramp that is 5.0 meters long. What is the magnitude of the
force applied to the box to do this work?
A) 15 N
B) 4.0 N
C) 20. N
D) 12 N
3)
A 500.-newton girl lifts a 10.-newton box vertically upward a distance of 0.50 meter. The work done on the box is
A) 5.0 J
B) 50. J
C) 2,500 J
D) 250 J
4)
How much work is done on a downhill skier by an average braking force of 9.8 x 10 2 newtons to stop her in a distance of 10. meters?
A)
5)
B)
9.8 x 10 3 J
3.8 x 10 6 J
B)
2.0 x 10 6 J
D) 1.0 x 10 3 J
C)
2.0 x 10 4 J
D) 3.8 x 10 4 J
C)
36 J
D) 18 J
The diagram below shows a 5.0-kilogram mass sliding 9.0 meters down an incline from a height of 2.0 meters in 3.0 seconds. The object gains
90. joules of kinetic energy while sliding.
How much work is done against friction as the mass slides the 9.0 meters?
A) 0 J
B) 90. J
8)
1.0 x 10 1 J
A box is pushed to the right with a varying horizontal force. The graph below represents the relationship between the applied force and the
distance the box moves.
What is the total work done in moving the box 6.0 meters?
A) 9.0 J
B) 27 J
7)
C)
A constant force of 1,900 newtons is required to keep an automobile having a mass of 1.0 x 10 3 kilograms moving at a constant speed of
20. meters per second. The work done in moving the automobile a distance of 2.0 x 10 3 meters is
A)
6)
9.8 x 10 1 J
C)
8J
D) 45 J
A 2.0-kilogram block sliding down a ramp from a height of 3.0 meters above the ground reaches the ground with a kinetic energy of 50. joules.
The total work done by friction on the block as it slides down the ramp is approximately
A) 6 J
B) 44 J
C) 9 J
D) 18 J
6634 - 1 - Page 2
9)
The graph below represents the elongation of a spring as a function of the applied force.
How much work must be done to stretch the spring 0.40 meter?
A) 9.8 J
B) 4.8 J
C)
24 J
D) 6.0 J
10)
Through what vertical distance is a 50.-newton object moved if 250 joules of work is done against the gravitational field of Earth?
A) 9.8 m
B) 25 m
C) 2.5 m
D) 5.0 m
11)
If the speed of a car is doubled, the kinetic energy of the car is
A) halved
B) doubled
12)
quadrupled
D) quartered
Which graph best represents the relationship between the kinetic energy of a moving object and its velocity?
A)
13)
C)
B)
C)
D)
The diagram below shows block A, having mass 2m and speed v, and block B having mass m and speed 2v.
Compared to the kinetic energy of block A, the kinetic energy of block B is
A) one-half as great
B) twice as great
C)
four times as great
D) the same
14)
A 45.0-kilogram boy is riding a 15.0-kilogram bicycle with a speed of 8.00 meters per second. What is the combined kinetic energy of the boy and
the bicycle?
A) 480. J
B) 240. J
C) 1,440 J
D) 1,920 J
15)
An object moving at a constant speed of 25 meters per second possesses 450 joules of kinetic energy. What is the object's mass?
A) 1.4 kg
B) 18 kg
C) 36 kg
D) 0.72 kg
16)
During an emergency stop, a 1.5 x 10 3-kilogram car lost a total of 3.0 x 10 5 joules of kinetic energy. What was the speed of the car at the moment
the brakes were applied?
A) 25 m/s
B) 20. m/s
C) 14 m/s
D) 10. m/s
17)
18)
6634 - 1 - Page 3
Which graph best represents the relationship between gravitational potential energy (PE) and height (h) above the ground for an object near the
surface of Earth?
A)
C)
B)
D)
Two vacationers walk out on a horizontal pier as shown in the diagram below.
As they approach the end of the pier, their gravitational potential energy will
A) decrease
B) increase
C)
remain the same
19)
Two students of equal weight go from the first floor to the second floor. The first student uses an elevator and the second student walks up a
flight of stairs. Compared to the gravitational potential energy gained by the first student, the gravitational potential energy gained by the second
student is
A) the same
B) greater
C) less
20)
A 1.0-kilogram book resting on the ground is moved 1.0 meter at various angles relative to the horizontal. In which direction does the 1.0-meter
displacement produce the greatest increase in the book's gravitational potential energy?
A)
C)
B)
D)
6634 - 1 - Page 4
21)
The graph below represents the kinetic energy, gravitational potential energy, and total mechanical energy of a moving block.
Which best describes the motion of the block?
A) falling freely
B) sliding up a frictionless incline
22)
23)
C) accelerating on a flat horizontal surface
D) being lifted at constant velocity
An object falls freely near Earth's surface. Which graph best represents the relationship between the object's kinetic energy and its time of fall?
A)
C)
B)
D)
The diagram below shows an ideal simple pendulum.
As the pendulum swings from position A to position B, what happens to its total mechanical energy? [Neglect friction.]
A) It increases.
B) It remains the same.
C) It decreases.
24)
A constant force is used to keep a block sliding at constant velocity along a rough horizontal track. As the block slides, there could be an increase
in its
A) gravitational potential energy and kinetic energy
C) gravitational potential energy, only
B) internal energy and kinetic energy
D) internal energy, only
25)
A 0.10-kilogram ball dropped vertically from a height of 1.00 meter above the floor bounces back to a height of 0.80 meter. What is the
mechanical energy lost by the ball as it bounces?
A) 0.30 J
B) 0.080 J
C) 0.20 J
D) 0.78 J
26)
A 55.0-kilogram diver falls freely from a diving platform that is 3.00 meters above the surface of the water in a pool. When she is 1.00 meter
above the water, what are her gravitational potential energy and kinetic energy with respect to the water's surface?
A) PE = 1,080 J and KE = 540 J
C) PE = 1,620 J and KE = 0 J
B) PE = 810 J and KE = 810 J
D) PE = 540 J and KE = 1,080 J
27)
A 1-kilogram rock is dropped from a cliff 90 meters high. After falling 20 meters, the kinetic energy of the rock is approximately
A) 200 J
B) 900 J
C) 20 J
D) 700 J
28)
As a spring is stretched, its elastic potential energy
A) remains the same
B)
decreases
C)
increases
29)
6634 - 1 - Page 5
A 3.0-kilogram mass is attached to a spring having a spring constant of 30. newtons per meter. The mass is pulled 0.20 meter from the spring's
equilibrium position and released. What is the maximum kinetic energy achieved by the mass-spring system?
A) 2.4 J
B) 1.5 J
C) 1.2 J
D) 0.60 J
30)
A spring has a spring constant of 120 newtons per meter. How much potential energy is stored in the spring as it is stretched 0.20 meter?
A) 4.8 J
B) 2.4 J
C) 12 J
D) 24 J
31)
The graph below represents the relationship between the work done by a student running up a flight of stairs and the time of ascent.
What does the slope of the given graph represent?
A) power
B) impulse
C)
speed
D) momentum
32)
A girl weighing 500. newtons takes 50. seconds to climb a flight of stairs 18 meters high. What is her vertical power output?
A) 180 W
B) 4,000 W
C) 9,000 W
D) 1,400 W
33)
A 40.-kilogram student runs up a staircase to a floor that is 5.0 meters higher than her starting point in 7.0 seconds. The student's power output is
A)
34)
1.4 x 10 4 W
B)
1.4 x 10 3 W
C)
29 W
D) 280 W
What is the average power developed by a motor as it lifts a 400.-kilogram mass at constant speed through a vertical distance of 10.0 meters in
8.0 seconds?
A) 4,900 W
B) 320 W
C) 32,000 W
D) 500 W