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- A nonzero net force acts on a particle and does work. This is the only force acting on the
particle. Which one of the following statements is true?
A) The kinetic energy of the particle changes, but the velocity of the particle does not
change.
B) The kinetic energy, speed, and velocity of the particle change.
C) The kinetic energy of the particle changes, but the speed of the particle does not
change.
D) The kinetic energy of the particle does not change, but the speed of the particle does
change.
E) The kinetic energy and the speed of the particle change, but the velocity of the particle
does not change.
- You are moving out of town and need to load a heavy box of mass m off of the ground
and into the back of the moving truck. You can either pick the box straight up and set it
in the truck (a height h above the ground) or slide the box a distance L up a ramp into the
back of the truck. Assume the ramp has good rollers on it, so that it is frictionless.
Which way of loading the box requires more work?
A) Lifting the box straight up off the ground requires more work.
B) Sliding the box up the roller-ramp requires more work.
C) Lifting the box straight up and sliding the box up the ramp require the same amount of
work.
D) It could be either… but you must know the mass m of the box to answer this question.
E) It could be either… but you must know the lengths L and h to answer this question.
- A beagle sits on the left end of a stationary raft in still water, as shown. The beagle gets
up, walks to the other end of the raft, and sits back down. The beagle and the raft have the
same mass. Which of the following statements is true? (You should neglect any drag
effects due to the water.)
A) The raft moved in the + x direction while the beagle was walking.
B) The raft moved in the - x direction while the beagle was walking.
C) The raft started moving in the + x direction after the beagle sits back down.
D) The raft started moving in the - x direction after the beagle sits back down.
E) The raft did not move from its original location at any time.
- In a game of pool, a cue ball strikes an eight ball head on. Before the collision the cue
ball is moving in the + x direction at 20 m/s while the eight ball is at rest. After the
collision, the cue ball is at rest while the eight ball is moving in the + x direction with a
speed of 20 m/s. Both the cue ball and the eight ball have the same mass. Which of the
following statements is true?
A) The collision is elastic because linear momentum is conserved.
B) The collision is inelastic because the two objects are rigid and do not compress or
stretch.
C) The collision is elastic because kinetic energy is conserved.
D) The collision is inelastic because one of the objects is stationary after the collision.
E) None of the above statements is true.
- Two children are riding on a spinning merry-go-round. Child A is at a greater distance
from the axis of rotation than child B. Which child has the larger angular displacement?
A) Child A
B) Child B
C) They have the same zero angular displacement.
D) They have the same non-zero angular displacement.
E) There is not enough information given to answer the question.
- A disk, a hoop, and a solid sphere are released at the same time at the top of an inclined
plane. They all roll without slipping. In what order do they reach the bottom?
A) disk, hoop, sphere
B) hoop, sphere, disk
C) sphere, disk, hoop
D) hoop, sphere, disk
E) hoop, disk, sphere
- The two rotating systems shown below differ only in where two identical movable
masses are positioned. On the left, they are positioned a distance r from the axis of
rotation, and on the right, they are positioned at r /2 from the axis of rotation. If you
release the hanging blocks simultaneously from rest at the same height,
A) the block at left lands first.
B) the block at right lands first.
C) both blocks land at the same time.
D) it is impossible to tell which block reaches the bottom first.
- The skateboarder in the drawing is moving down the left side of the ramp with an initial
speed v
o
. The highest point reached by the skateboarder on the right side of the ramp is h
= 1.18 m. What is v
o
? (Neglect nonconservative forces, such as friction and air
resistance.)
A) 2.19 m/s
B) 3.10 m/s
C) 5.05 m/s
D) 4.81 m/s
E) 6.79 m/s
- Earth's radius is 6.38 × 10
m, and it completes one revolution every day. What is the
tangential speed of a person standing on the equator?
A) 232 m/s
B) 148 m/s
C) 464 m/s
D) 21.5 m/s
E) 73.8 m/s
- A solid sphere is rolling without slipping along a horizontal surface with a speed of 5.
m/s when it starts up a ramp that makes an angle of 25.0° with the horizontal. What is the
speed of the sphere after it has rolled 3.00 m up the ramp? Notice the sphere rises a
height h as it rolls up the ramp.
A) 4.01 m/s
B) 8.02 m/s
C) 1.91 m/s
D) 2.16 m/s
E) 3.53 m/s
- A wheel that is rotating at 33.3 rad/s is given an angular acceleration of 2.15 rad/s
Through what angle has the wheel turned when its angular speed reaches 72.0 rad/s?
A) 83.2 rad
B) 316 rad
C) 697 rad
D) 66.8 rad
E) 948 rad
o
3.00 m
h v o
v f
ω o
ω f
v
o
- A cat named SchrÖdinger walks along a uniform plank that is 4.00 m long and has a
mass of 7.00 kg. The plank is supported by two sawhorses, one that is 0.44 m from the
left end of the plank, and the other that is 1.50 m from the right end. When the cat
reaches the very right end of the plank, the plank starts to tip. What is Schrodinger’s
mass? Note: Just when the plank begins to tip, the normal force on the plank from the
sawhorse on the left will go to zero.
A) 7.00 kg
B) 4.62 kg
C) 3.08 kg
D) 2.33 kg
E) 0.429 kg
1.5 0 m
4.00 m
