Download Test Review Packet- Newton`s Laws and Friction

1. Compared to the inertia of a 1-kilogram mass, the inertia of a 4-kilogram mass is
a. 1/4 as great
b. 1/16 as great
c. 16 times as great
d. 4 times as great
2. Box M is on a frictionless table with forces F1 and F2 acting as shown below.
If the magnitude of F1 is greater than the magnitude of F2, then the box is
a. b. c. d. moving with a constant speed in the direction of F1 moving with a constant speed in the direction of F2
accelerating in the direction of F1
accelerating in the direction of F2
3. A 1.2 × 103-kilogram automobile in motion strikes a 1.0 × 10-4-kilogram insect. As a result, the insect is accelerated at a
rate of 1.0 × 102 m/s2. What is the magnitude of the force the insect exerts on the car?
a. b. c. d. 1.0 × 10-2 N
1.2 × 10-2 N
1.0 × 101 N
1.2 × 103 N
4. The table lists the coefficients of kinetic friction for four materials sliding over steel.
A 10.-kilogram block of each of the materials in the table is pulled horizontally across a steel floor at constant velocity. Which
block would require the smallest applied force to keep it moving at constant velocity?
a. b. c. d. aluminum
brass
copper
steel
5. A copper coin resting on a piece of cardboard is placed on a beaker as shown in the diagram. When the cardboard is
rapidly removed, the coin drops into the beaker.
The two properties of the coin which best explain its fall are its weight and its
a. b. c. d. temperature
electrical resistance
volume
inertia
6. An object with a mass of 0.5 kilogram starts from rest and achieves a maximum speed of 20 meters per second in 0.01
second. What average unbalanced force accelerates this object?
a. 1,000 N
b. 10 N
c. 0.1 N
d. 0.001 N
7. Four forces are acting on an object as shown in the diagram.
If the object is moving with a constant velocity, the magnitude of force F must be
a. b. c. d. 0 N
20 N
100 N
40 N
8. A 50.-kilogram student stands on the surface of the Earth. What is the magnitude of the gravitational force of the Earth on the
student?
a. 490 N
b. 50. N
c. 9.8 N
d. 6.7 × 10-11 N
9. A net force of 5.0 × 102 newtons causes an object to accelerate at a rate of 5.0 meters per second per second. What is the
mass of the object?
a. b. c. d. 1.0 × 102 kg
2.0 × 10-1 kg
6.0 × 102 kg
2.5 × 103 kg
10. Which statement explains why a book resting on a table is in equilibrium?
a. There is a net force acting downward on the book.
b. The weight of the book equals the weight of the table.
c. The acceleration due to gravity is 9.8 m/s2 for both the book and the table.
d. The weight of the book and the table's upward force on the book are equal in magnitude, but opposite in direction.
11. A 60.-kilogram astronaut weighs 96 newtons on the surface of the Moon. The acceleration due to gravity on the Moon is
a. b. c. d. 0.0 m/s2
1.6 m/s2
4.9 m/s2
9.8 m/s2
12. Two forces are applied to a 2.0-kilogram block on a frictionless, horizontal surface, as shown in the diagram. The acceleration of the block is
a. b. c. d. 5.0 m/s2 to the right
5.0 m/s2 to the left
3.0 m/s2 to the right
3.0 m/s2 to the left
13. As shown in the diagram, an inflated balloon released from rest moves horizontally with velocity v . The velocity of the balloon is most likely caused by
a. b. c. d. action-reaction force
centripetal force
gravitational attraction
rolling friction
14. A horizontal force is used to pull a 5.0-kilogram cart at a constant speed of 5.0 meters per second across the floor, as
shown in the diagram.
If the force of friction between the cart and the floor is 10. newtons, the magnitude of the horizontal force along the handle of the
cart is
a. b. c. d. 5.0 N
10. N
25 N
50. N
15. In the diagram below, surface B of the wooden block has the same texture as surface A, but twice the area of surface A.
If force F is required to slide the block at constant speed across the table on surface A, approximately what force is required to
slide the block at constant speed across the table on surface B?
a. F
b. 2F
c. d. 4F
16. On the surface of planet X, the acceleration due to gravity is 16 meters per second2. What is the weight of a 6.0-kilogram
mass located on the surface of planet X?
a. 2.7 N
b. 59 N
c. 96 N
d. 940 N
17. A person kicks a 4.0-kilogram door with a 48-newton force causing the door to accelerate at 12 meters per second2. What is the magnitude of the force exerted by the door on the person?
a. 48 N
b. 24 N
c. 12 N
d. 4.0 N
18. If a 30-newton force is required to accelerate a 2-kilogram object at 10 meters per second2, over a level floor, then the
magnitude of the frictional force acting on the object is
a. 0 N
b. 10 N
c. 20 N
d. 30 N
19. A tennis ball is hit with a tennis racket. Compared to the force of the racket on the ball, the force of the ball on the racket is
a. smaller
b. larger
c. the same
20. A 15-kilogram mass weighs 60. newtons on planet X. The mass is allowed to fall freely from rest near the surface of the
planet. After falling for 6.0 seconds, the acceleration of the mass is
a. b. c. d. 0.25 m/s2
10. m/s2
24 m/s2
4.0 m/s2
21. The diagram below shows a granite block being slid at constant speed across a horizontal concrete floor by a force parallel
to the floor.
Which pair of quantities could be used to determine the coefficient of friction for the granite on the concrete?
a. b. c. d. mass and speed of the block
mass and normal force on the block
frictional force and speed of the block
frictional force and normal force on the block
Figure 1
Base your answer to the question on the information and diagram.
A 10.-kilogram box, sliding to the right across a rough horizontal floor, accelerates at -2.0 meters per second2 due to the force
of friction.
22. [Refer to figure 1]
(a) Calculate the magnitude of the net force acting on the box.
Answer: N
(b) Calculate the coefficient of kinetic friction between the box and the floor.
Answer: μ = 23. Compared to the force needed to start sliding a crate across a rough level floor, the force needed to keep it sliding once it is
moving is
a. less
b. greater
c. the same
24. A 10.-kilogram rubber block is pulled horizontally at constant velocity across a sheet of ice. Calculate the magnitude of the
force of friction acting on the block. Round your answer to the nearest tenth of a newton.
Answer: Ff = N
25. Base your answer to the question on the information and diagram below.
A horizontal force of 8.0 newtons is used to pull a 20.-newton wooden box moving toward the right along a horizontal, wood
surface, as shown.
The diagram below shows the vector representing the normal force acting on the box.
Normal Force Acting on Box
a) Calculate the magnitude of the frictional force acting on the box.
Answer: Ff = N
b) Determine the magnitude of the net force acting on the box.
Answer: N
c) Determine the mass of the box.
Answer: kg
d) Calculate the magnitude of the acceleration of the box.
Answer: a = m/s2
26. A car’s performance is tested on various horizontal road surfaces. The brakes are applied, causing the rubber tires of the
car to slide along the road without rolling. The tires encounter the greatest force of friction to stop the car on
a. dry concrete
b. dry asphalt
c. wet concrete
d. wet asphalt
27. A carpenter hits a nail with a hammer. Compared to the magnitude of the force the hammer exerts on the nail, the magnitude
of the force the nail exerts on the hammer during contact is
a. less
b. greater
c. the same
28. Two forces, F1 and F2, are applied to a block on a frictionless, horizontal surface as shown below.
If the magnitude of the block’s acceleration is 2.0 meters per second2, what is the mass of the block?
a. b. c. d. 1 kg
5 kg
6 kg
7 kg
Figure 2
Base your answer to this question on the information below. An ice skater applies a horizontal force to a 20.-kilogram block on frictionless, level ice, causing the block to accelerate
uniformly at 1.4 meters per second2 to the right. After the skater stops pushing the block, it slides onto a region of ice that is
covered with a thin layer of sand. The coefficient of kinetic friction between the block and the sand-covered ice is 0.28.
29. [Refer to figure 2]
Determine the magnitude of the normal force acting on the block.
× 102 N
Answer: 30. [Refer to figure 2]
Calculate the magnitude of the force of friction acting on the block as it slides over the sand-covered ice.
Answer: N
31. Two forces act concurrently on an object on a horizontal, frictionless surface, as shown in the diagram below.
What additional force, when applied to the object, will establish equilibrium?
a. b. c. d. 16 N toward the right
16 N toward the left
4 N toward the right
4 N toward the left
32. An 8.0-newton wooden block slides across a horizontal wooden floor at constant velocity. What is the magnitude of the
force of kinetic friction between the block and the floor?
a. 2.4 N
b. 3.4 N
c. 8.0 N
d. 27 N
Figure 3
Base your answer to the question on the information below and on your knowledge of physics.
A horizontal 20.-newton force is applied to a 5.0-kilogram box to push it across a rough, horizontal floor at a constant
velocity of 3.0 meters per second to the right.
33. [Refer to figure 3]
Determine the magnitude of the force of friction acting on the box.
Answer: N
34. [Refer to figure 3]
Calculate the weight of the box. [Show all work, including the equation and substitution with units.]
35. [Refer to figure 3]
Calculate the coefficient of kinetic friction between the box and the floor. [Show all work, including the equation and substitution
with units]