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AP Quiz: Newton’s 2nd law
1. A 0.50-kilogram puck sliding on a horizontal shuffleboard court is slowed to rest by a frictional force
of 1.2 newtons. What is the coefficient of kinetic friction between the puck and the surface of the
shuffleboard court?
A. 0.24
B. 0.42
C. 0.60
D. 4.1
2. The diagram below shows a 4.0-kilogram object
accelerating at 5.0 meters per second2 on a rough
horizontal surface. What is the magnitude of the
frictional force Ff acting on the object?
A. 5.0 N
B. 50. N
C. 20. N
D. 30. N
5 m/s2
3. A 1.0-kilogram block is placed on each of four frictionless planes inclined at different angles. On
which inclined plane will the normal force be greatest?
4. A man weighs 800 newtons standing on a scale in a stationary elevator. He notices that the scale
registers a weight 30 newtons lighter when the elevator is moving. The elevator is experiencing which of
the following?
A. constant acceleration downward
B. constant speed downward
C. constant acceleration upward
D. constant speed upward
5. A 2,400-kilogram car is traveling at a speed of 20. meters per second. Compared to the magnitude of
the force required to stop the car in 6.0 seconds, the magnitude of the force required to stop the car in 12
seconds is
A. half as great
B. the same
C. twice as great
D. four times as great
6. A box of mass m slides along a horizontal floor with constant velocity v. The coefficient of kinetic
friction between the box and the floor is . What is the net force on the box?
A. mgv
B. mgv
C. mv
D. zero
7. A person pushes a block of mass M = 6.0kg with a constant
speed straight up a flat surface inclined 30.0° above the
horizontal. The coefficient of kinetic friction between the block
and the surface is μ = 0.40. What is the approximate pushing
force, F, acting on the block?
(A) 60 N
(B) 21 N
(C) 30 N
(D) 51 N
8. A block weighing 100 Newtons is resting on a horizontal surface. The coefficients of static and kinetic
friction between the block and surface are 0.4 and 0.2, respectively. A horizontal force of 41 Newtons is
exerted on the block toward the right. Which of the following statements correctly describes the motion of
the block?
A. The block will accelerate to the right at a rate of 0.1 m/s2.
B. The block will accelerate to the right at a rate of 2.1 m/s2.
C. The block will accelerate to the right at a rate of 1 m/s2.
D. The block will remain at rest.
9. During a collision, an 84-kilogram driver of a car moving at 24 meters per second is brought to rest by
an inflating air bag in 1.2 seconds. The magnitude of the force exerted on the driver by the air bag is
approximately
A. 7.0 × 101 N
B. 8.2 × 102 N
C. 1.7 × 103 N
D. 2.0 × 103 N
10.A 6.0-kilogram block, sliding to the east across a horizontal, frictionless surface with a momentum of
50. kilogram•meters per second, strikes an obstacle. The obstacle exerts an impulse of 20.newton•seconds
to the west on the block. The speed of the block after the collision is
A. 3.3 m/s
B. 5.0 m/s
C. 12. m/s
D. 20. m/s
11. A student drops two eggs of equal mass simultaneously from the same height. Egg A lands
on the tile floor and breaks. Egg B lands intact, without bouncing, on a foam pad lying on the
floor. Compared to the magnitude of the impulse on egg A as it lands, the magnitude of the
impulse on egg B as it lands is
A. less
B. greater
C. the same
12.How does an air mattress protect a stunt person landing on the ground after a stunt?
A. It reduces the momentum change of the stunt person.
B. It increases the momentum change of the stunt person.
C. It shortens the stopping time of the stunt person and increases the force applied during the
landing.
D. It lengthens the stopping time of the stunt person and reduces the force applied during the
landing.
13. A hockey puck is sliding to the right on a floor in a long hallway. It slows down and eventually stops
20 meters down the hall. Which of the following freebody diagrams shows the forces acting on the puck
as it slides down the hallway?
14. The graph below shows the force acting on a 2kg object over a 5 second interval.
a. Calculate the magnitude of the change of momentum over the 5 second interval.[2]
b. Is the object speeding up or slowing down? Give evidence from the graph.[2]
15. A manufacturer’s advertisement claims that their 1,250-kilogram (12,300-newton) sports car can
accelerate on a level road from 0 to 60.0 miles per hour (0 to 26.8 meters per second) in 3.75 seconds.
a) Calculate the net force required to give the car the acceleration claimed in the advertisement. [2]
b) The coefficient of static friction between the car’s tires and the road is 0.80. Explain whether or
not the manufacturer’s claim about the car will be possible. [2]
16. A child pulls a 10 kg wagon at a constant acceleration of 0.5
m/s2 along a level sidewalk. The child does this by applying a 22newton force to the wagon handle, which is inclined at 35° to the
sidewalk as shown. Determine the force of friction acting on the
wagon. [2]
17. An 85 kg skydiver pulls the parachute and begins accelerating upward at 2.5
m/s2. What is the drag force acting on the parachute at this point? [2]
18. Truck A is heavier than B and crashes into the back of
truck B. During the collision, is the impulse that truck A
receives greater, less or equal to the impulse that B
receives? Explain your reasoning. [2]
19. The figures below show four situations where the same block, which has a mass of 5 kg, remains at
rest on either a horizontal or an inclined surface. The surfaces are all made of the same material. In all
cases except Case A, a 4 N force acts on the block parallel to the surface as indicated by the arrow in the
diagram. [2]
A
B
4N
D
E
C
4N
28°
4N
20°
F
4N
4N
28°
Rank these situations on the basis of the magnitude of the frictional force on the block.
Greatest
1 _______ 2 _______ 3 _______ 4 _______
Least
OR, The magnitude of the frictional force is the same but not zero for all these cases.
___
OR, The magnitude of the frictional force is zero for all these cases.
___
OR, We cannot determine the ranking for the magnitude of these frictional forces.
___
Please explain your reasoning.