Question 1

A 6.0-kg object is suspended by a vertical string from the ceiling of an elevator which is accelerating upward at a rate of 1.8 m/s2. Determine the tension in the string.

Accepted Answer

A)  11 N 
B)  70 N 
C)  48 N 
D)  59 N 
E)  62 N 
A)  11 N 
B)  70 N 
C)  48 N 
D)  59 N 
E)  62 N

Question 2

Only two forces act on a 3.0-kg mass. One of the forces is 9.0 N east, and the other is 8.0 N in the direction of 62° north of west. What is the magnitude of the acceleration of the mass?

Accepted Answer

A)  2.0 m/s2 
B)  2.4 m/s2 
C)  3.3 m/s2 
D)  2.9 m/s2 
E)  5.7 m/s2 
A)  2.0 m/s2 
B)  2.4 m/s2 
C)  3.3 m/s2 
D)  2.9 m/s2 
E)  5.7 m/s2

Question 3

If P = 6.0 N, what is the magnitude of the force exerted on block 1 by block 2?

Accepted Answer

A)  6.4 N 
B)  5.6 N 
C)  4.8 N 
D)  7.2 N 
E)  8.4 N 
A)  6.4 N 
B)  5.6 N 
C)  4.8 N 
D)  7.2 N 
E)  8.4 N

Question 4

A 1.5-kg object has a velocity of 5   m/s at t = 0. It is accelerated at a constant rate for five seconds after which it has a velocity of (6   + 12   ) m/s. What is the magnitude of the resultant force acting on the object during this time interval?

Accepted Answer

A)  3.8 N 
B)  3.2 N 
C)  2.8 N 
D)  4.3 N 
E)  4.6 N 
A)  3.8 N 
B)  3.2 N 
C)  2.8 N 
D)  4.3 N 
E)  4.6 N

Question 5

If M = 2.2 kg, what is the tension in the connecting string? The pulley and all surfaces are frictionless.

Accepted Answer

A)  6.4 N 
B)  5.9 N 
C)  5.4 N 
D)  6.9 N 
E)  8.3 N 
A)  6.4 N 
B)  5.9 N 
C)  5.4 N 
D)  6.9 N 
E)  8.3 N

Question 6

If F = 40 N and M = 1.5 kg, what is the tension in the string connecting M and 2M? Assume that all surfaces are frictionless.

Accepted Answer

A)  13 N 
B)  23 N 
C)  36 N 
D)  15 N 
E)  28 N 
A)  13 N 
B)  23 N 
C)  36 N 
D)  15 N 
E)  28 N

Question 7

The first of two identical boxes of mass m is sitting on level ground. The second box is sitting on a ramp that makes a 20° angle with the ground. The normal force of the level ground on the first box is NL; the normal force of the ramp on the second box is NR. Which statement is correct?

Accepted Answer

A)  NR = NL = mg. 
B)  NL = mg; NR = mg sin 20°. 
C)  NL = mg; NR = mg cos 20°. 
D)  NL = mg; NR = −mg cos 20°. 
E)  NR = −NL = −mg. 
A)  NR = NL = mg. 
B)  NL = mg; NR = mg sin 20°. 
C)  NL = mg; NR = mg cos 20°. 
D)  NL = mg; NR = −mg cos 20°. 
E)  NR = −NL = −mg.

Question 8

A catcher arranges to catch a baseball dropped from a height 50 m above his glove. However, his friends substitute a soft 250 g red grapefruit, so that it will smash apart when he catches it. His glove stops the grapefruit in 0.010 s. What force does the glove exert on the grapefruit?

Accepted Answer

A)  0.078 3 N 
B)  783 N 
C)  2 450 N 
D)  24 500 N 
E)  78 300 N 
A)  0.078 3 N 
B)  783 N 
C)  2 450 N 
D)  24 500 N 
E)  78 300 N

Question 9

A 1.0-kg block is pushed up a rough 22° inclined plane by a force of 7.0 N acting parallel to the incline. The acceleration of the block is 1.4 m/s2 up the incline. Determine the magnitude of the force of friction acting on the block.

Accepted Answer

A)  1.9 N 
B)  2.2 N 
C)  1.3 N 
D)  1.6 N 
E)  3.3 N 
A)  1.9 N 
B)  2.2 N 
C)  1.3 N 
D)  1.6 N 
E)  3.3 N

Question 10

A 6.00 kg block is placed on a 30.0° incline and connected to another block on a 36.87° incline. Although the surfaces are frictionless the blocks do not move. What is the mass in kilograms of the block on the 36.87° incline?

Accepted Answer

A)  1.80 
B)  3.00 
C)  4.00 
D)  5.00 
E)  6.00 
A)  1.80 
B)  3.00 
C)  4.00 
D)  5.00 
E)  6.00

Question 11

In a game of shuffleboard (played on a horizontal surface), a puck is given an initial speed of 6.0 m/s. It slides a distance of 9.0 m before coming to rest. What is the coefficient of kinetic friction between the puck and the surface?

Accepted Answer

A)  0.20 
B)  0.18 
C)  0.15 
D)  0.13 
E)  0.27 
A)  0.20 
B)  0.18 
C)  0.15 
D)  0.13 
E)  0.27

Question 12

If the only forces acting on a 2.0-kg mass are   N and   N, what is the magnitude of the acceleration of the particle?

Accepted Answer

A)  1.5 m/s2 
B)  6.5 m/s2 
C)  4.7 m/s2 
D)  9.4 m/s2 
E)  7.2 m/s2 
A)  1.5 m/s2 
B)  6.5 m/s2 
C)  4.7 m/s2 
D)  9.4 m/s2 
E)  7.2 m/s2

Question 13

A 1.8-kg block is projected up a rough 10° inclined plane. As the block slides up the incline, its acceleration is 3.8 m/s2 down the incline. What is the magnitude of the force of friction acting on the block?

Accepted Answer

A)  5.0 N 
B)  3.8 N 
C)  4.2 N 
D)  4.6 N 
E)  6.5 N 
A)  5.0 N 
B)  3.8 N 
C)  4.2 N 
D)  4.6 N 
E)  6.5 N

Question 14

When an acrobat hangs motionless from a pair of rings

Accepted Answer

A)  she has no measurable weight. 
B)  her weight depends on the angles the ropes make with the ceiling. 
C)  her weight is reduced by the upward force the rings exert on her. 
D)  her weight is increased by the upward force the rings exert on her. 
E)  she exerts a gravitational force on the Earth that is equal to the sum of the forces the rings exert on her. 
A)  she has no measurable weight. 
B)  her weight depends on the angles the ropes make with the ceiling. 
C)  her weight is reduced by the upward force the rings exert on her. 
D)  her weight is increased by the upward force the rings exert on her. 
E)  she exerts a gravitational force on the Earth that is equal to the sum of the forces the rings exert on her.

Question 15

A block is pushed across a horizontal surface by the force shown. If the coefficient of kinetic friction between the block and the surface is 0.30, F = 20 N, θ = 30°, and M = 3.0 kg, what is the magnitude of the acceleration of the block?

Accepted Answer

A)  2.8 m/s2 
B)  2.3 m/s2 
C)  1.8 m/s2 
D)  3.3 m/s2 
E)  5.4 m/s2 
A)  2.8 m/s2 
B)  2.3 m/s2 
C)  1.8 m/s2 
D)  3.3 m/s2 
E)  5.4 m/s2

Question 16

A book is resting on a table. How many forces would be in the free-body diagram of the book?

Accepted Answer

A)  one 
B)  two of the same type 
C)  two of different types 
D)  three or more of the same type 
E)  three or more of at least two different types 
A)  one 
B)  two of the same type 
C)  two of different types 
D)  three or more of the same type 
E)  three or more of at least two different types

Question 17

A heavy weight is supported by two cables that exert tensions of magnitude T1 and T2. Which statement is correct?

Accepted Answer

A)  T1 = T2. 
B)  T1y = T2y. 
C)  T1 > T2. 
D)  T1 2. 
E)  We need the mass of the box in order to determine the correct answer. 
A)  T1 = T2. 
B)  T1y = T2y. 
C)  T1 > T2. 
D)  T1 2. 
E)  We need the mass of the box in order to determine the correct answer.

Question 18

In the figure shown, the coefficient of kinetic friction between the block and the incline is 0.29. What is the magnitude of the acceleration of the suspended block as it falls? Disregard any pulley mass or friction in the pulley.

Accepted Answer

A)  5.4 m/s2 
B)  5.2 m/s2 
C)  4.9 m/s2 
D)  5.6 m/s2 
E)  7.9 m/s2 
A)  5.4 m/s2 
B)  5.2 m/s2 
C)  4.9 m/s2 
D)  5.6 m/s2 
E)  7.9 m/s2

Question 19

A 2.0-kg block slides on a rough horizontal surface. A force (magnitude P = 4.0 N) acting parallel to the surface is applied to the block. The magnitude of the block's acceleration is 1.2 m/s2. If P is increased to 5.0 N, determine the magnitude of the block's acceleration.

Accepted Answer

A)  2.1 m/s2 
B)  2.3 m/s2 
C)  1.9 m/s2 
D)  1.7 m/s2 
E)  3.2 m/s2 
A)  2.1 m/s2 
B)  2.3 m/s2 
C)  1.9 m/s2 
D)  1.7 m/s2 
E)  3.2 m/s2

Question 20

An object of unknown weight is suspended as shown. The tension in rope 1 is 25 lb, and the tension in rope 2 is 31 lb. What is the weight of the suspended object?

Accepted Answer

A)  36 lb 
B)  33 lb 
C)  41 lb 
D)  39 lb 
E)  56 lb 
A)  36 lb 
B)  33 lb 
C)  41 lb 
D)  39 lb 
E)  56 lb

Exam 5: The Laws of Motion

A 6.0-kg object is suspended by a vertical string from the ceiling of an elevator which is accelerating upward at a rate of 1.8 m/s2. Determine the tension in the string.

Only two forces act on a 3.0-kg mass. One of the forces is 9.0 N east, and the other is 8.0 N in the direction of 62° north of west. What is the magnitude of the acceleration of the mass?

If P = 6.0 N, what is the magnitude of the force exerted on block 1 by block 2?

A 1.5-kg object has a velocity of 5 m/s at t = 0. It is accelerated at a constant rate for five seconds after which it has a velocity of (6 + 12 ) m/s. What is the magnitude of the resultant force acting on the object during this time interval?

If M = 2.2 kg, what is the tension in the connecting string? The pulley and all surfaces are frictionless.

If F = 40 N and M = 1.5 kg, what is the tension in the string connecting M and 2M? Assume that all surfaces are frictionless.

The first of two identical boxes of mass m is sitting on level ground. The second box is sitting on a ramp that makes a 20° angle with the ground. The normal force of the level ground on the first box is NL; the normal force of the ramp on the second box is NR. Which statement is correct?

A catcher arranges to catch a baseball dropped from a height 50 m above his glove. However, his friends substitute a soft 250 g red grapefruit, so that it will smash apart when he catches it. His glove stops the grapefruit in 0.010 s. What force does the glove exert on the grapefruit?

A 1.0-kg block is pushed up a rough 22° inclined plane by a force of 7.0 N acting parallel to the incline. The acceleration of the block is 1.4 m/s2 up the incline. Determine the magnitude of the force of friction acting on the block.

A 6.00 kg block is placed on a 30.0° incline and connected to another block on a 36.87° incline. Although the surfaces are frictionless the blocks do not move. What is the mass in kilograms of the block on the 36.87° incline?

In a game of shuffleboard (played on a horizontal surface), a puck is given an initial speed of 6.0 m/s. It slides a distance of 9.0 m before coming to rest. What is the coefficient of kinetic friction between the puck and the surface?

If the only forces acting on a 2.0-kg mass are N and N, what is the magnitude of the acceleration of the particle?

A 1.8-kg block is projected up a rough 10° inclined plane. As the block slides up the incline, its acceleration is 3.8 m/s2 down the incline. What is the magnitude of the force of friction acting on the block?

When an acrobat hangs motionless from a pair of rings

A block is pushed across a horizontal surface by the force shown. If the coefficient of kinetic friction between the block and the surface is 0.30, F = 20 N, θ = 30°, and M = 3.0 kg, what is the magnitude of the acceleration of the block?

A book is resting on a table. How many forces would be in the free-body diagram of the book?

A heavy weight is supported by two cables that exert tensions of magnitude T1 and T2. Which statement is correct?

In the figure shown, the coefficient of kinetic friction between the block and the incline is 0.29. What is the magnitude of the acceleration of the suspended block as it falls? Disregard any pulley mass or friction in the pulley.

A 2.0-kg block slides on a rough horizontal surface. A force (magnitude P = 4.0 N) acting parallel to the surface is applied to the block. The magnitude of the block's acceleration is 1.2 m/s2. If P is increased to 5.0 N, determine the magnitude of the block's acceleration.

An object of unknown weight is suspended as shown. The tension in rope 1 is 25 lb, and the tension in rope 2 is 31 lb. What is the weight of the suspended object?

Physics and Measurement

Motion in One Dimension

Vectors

Motion in Two Dimensions

Circular Motion and Other Applications of Newtons Laws

Energy of a System

Conservation of Energy

Linear Momentum and Collisions

Rotation of a Rigid Object About a Fixed Axis

Angular Momentum

Static Equilibrium and Elasticity

Universal Gravitation

Fluid Mechanics

Oscillatory Motion

Wave Motion

Superposition and Standing Waves

Temperature

The First Law of Thermodynamics

The Kinetic Theory of Gases

Heat Engines, Entropy, and the Second Law of Thermodynamics

Electric Fields

Gausss Law

Electric Potential

Capacitance and Dielectrics

Current and Resistance

Direct-Current Circuits

Magnetic Fields

Sources of the Magnetic Field

Faradays Law

Inductance

Alternating-Current Circuits

Electromagnetic Waves

The Nature of Light and the Principles of Ray Optics

Image Formation

Wave Optics

Diffraction Patterns and Polarization

Relativity

Introduction to Quantum Physics

Quantum Mechanics

Atomic Physics

Molecules and Solids

Nuclear Structure

Particle Physics and Cosmology

Filters

A 6.0-kg object is suspended by a vertical string from the ceiling of an elevator which is accelerating upward at a rate of 1.8 m/s². Determine the tension in the string.

The first of two identical boxes of mass m is sitting on level ground. The second box is sitting on a ramp that makes a 20° angle with the ground. The normal force of the level ground on the first box is N_L; the normal force of the ramp on the second box is N_R. Which statement is correct?

A 1.0-kg block is pushed up a rough 22° inclined plane by a force of 7.0 N acting parallel to the incline. The acceleration of the block is 1.4 m/s² up the incline. Determine the magnitude of the force of friction acting on the block.

A 1.8-kg block is projected up a rough 10° inclined plane. As the block slides up the incline, its acceleration is 3.8 m/s² down the incline. What is the magnitude of the force of friction acting on the block?

A heavy weight is supported by two cables that exert tensions of magnitude T₁ and T₂. Which statement is correct?

A 2.0-kg block slides on a rough horizontal surface. A force (magnitude P = 4.0 N) acting parallel to the surface is applied to the block. The magnitude of the block's acceleration is 1.2 m/s². If P is increased to 5.0 N, determine the magnitude of the block's acceleration.