Question 1

An 1100-kg car traveling at 27.0 m/s starts to slow down and comes to a complete stop in 578 m.What is the magnitude of the average braking force acting on the car?

Accepted Answer

A) 690 N 
B) 550 N 
C) 410 N 
D) 340 N 
A) 690 N 
B) 550 N 
C) 410 N 
D) 340 N A

Question 2

A child on a sled starts from rest at the top of a 15° slope.If the trip to the bottom takes   how long is the slope? Assume that frictional forces may be neglected.

Accepted Answer

A) 293 m 
B) 586 m 
C) 1130 m 
D) 147 m 
A) 293 m 
B) 586 m 
C) 1130 m 
D) 147 m A

Question 3

On its own,a certain tow-truck has a maximum acceleration of 3.0 m/s2.What would be the maximum acceleration when this truck was towing a bus of twice its own mass?

Accepted Answer

A) 2.5 m/s2 
B) 2.0 m/s2 
C) 1.5 m/s2 
D) 1.0 m/s2 
A) 2.5 m/s2 
B) 2.0 m/s2 
C) 1.5 m/s2 
D) 1.0 m/s2 D

Question 4

Two forces act on a   object.One force has magnitude 65 N directed 59° clockwise from the positive x-axis,and the other has a magnitude 35 N at 32° clockwise from the positive y-axis.What is the magnitude of this object's acceleration?

Accepted Answer

A) 1.1 m/s2 
B) 1.3 m/s2 
C) 1.5 m/s2 
D) 1.7 m/s2 
A) 1.1 m/s2 
B) 1.3 m/s2 
C) 1.5 m/s2 
D) 1.7 m/s2

Question 5

Suppose you are playing hockey on a new-age ice surface for which there is no friction between the ice and the hockey puck.You wind up and hit the puck as hard as you can.After the puck loses contact with your stick,the puck will

Accepted Answer

A) start to slow down. 
B) not slow down or speed up. 
C) speed up a little,and then slow down. 
D) speed up a little,and then move at a constant speed. 
A) start to slow down. 
B) not slow down or speed up. 
C) speed up a little,and then slow down. 
D) speed up a little,and then move at a constant speed.

Question 6

An object is moving forward with a constant velocity.Which statement about this object MUST be true?

Accepted Answer

A) The net force on the object is zero. 
B) The net force on the object is in the forward direction. 
C) No forces are acting on the object. 
D) The acceleration of the object is in the forward direction. 
A) The net force on the object is zero. 
B) The net force on the object is in the forward direction. 
C) No forces are acting on the object. 
D) The acceleration of the object is in the forward direction.

Question 7

The figure shows two forces acting on an object,with magnitudes   and    What third force will cause the object to be in equilibrium (acceleration equals zero)?

Accepted Answer

A) 52 N pointing down 
B) 52 N pointing up 
C) 82 N pointing down 
D) 82 N pointing up 
A) 52 N pointing down 
B) 52 N pointing up 
C) 82 N pointing down 
D) 82 N pointing up

Question 8

Which one of the following free-body diagrams best represents the free-body diagram,with correct relative force magnitudes,of a person in an elevator that is traveling upward with an unchanging velocity?   f is the force of the floor on the person and   g is the force of gravity on the person.

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 9

You are standing in a moving bus,facing forward,and you suddenly fall forward as the bus comes to an immediate stop.The force acting on you that causes you to fall forward is

Accepted Answer

A) the force of gravity. 
B) the normal force due to your contact with the floor of the bus. 
C) the force due to static friction between you and the floor of the bus. 
D) the force due to kinetic friction between you and the floor of the bus. 
E) No forces were acting on you to cause you to fall. 
A) the force of gravity. 
B) the normal force due to your contact with the floor of the bus. 
C) the force due to static friction between you and the floor of the bus. 
D) the force due to kinetic friction between you and the floor of the bus. 
E) No forces were acting on you to cause you to fall.

Question 10

An object is moving to the right,and experiencing a net force that is directed to the right.The magnitude of the force is decreasing with time.The speed of the object is

Accepted Answer

A) increasing. 
B) decreasing. 
C) constant in time. 
A) increasing. 
B) decreasing. 
C) constant in time.

Question 11

If a 5.0 kg box is pulled simultaneously by a 10.0 N force and a 5.0 N force,then its acceleration must be

Accepted Answer

A) 3.0 m/s2. 
B) 2.2 m/s2. 
C) 1.0 m/s2. 
D) We cannot tell from the information given. 
A) 3.0 m/s2. 
B) 2.2 m/s2. 
C) 1.0 m/s2. 
D) We cannot tell from the information given.

Question 12

The figure shows an acceleration-versus-force graph for three objects pulled by rubber bands.The mass of object 2 is 36 kg.What are the masses of objects 1 and 3?

Accepted Answer

A) 14 kg and 90 kg 
B) 72 kg and 18 kg 
C) 90 kg and 18 kg 
D) 14 kg and 72 kg 
A) 14 kg and 90 kg 
B) 72 kg and 18 kg 
C) 90 kg and 18 kg 
D) 14 kg and 72 kg

Question 13

You are seated in a bus and notice that a hand strap that is hanging from the ceiling hangs away from the vertical in the backward direction.From this observation,you can conclude that

Accepted Answer

A) the velocity of the bus is forward. 
B) the velocity of the bus is backward. 
C) You cannot conclude anything about the direction of the velocity of the bus. 
A) the velocity of the bus is forward. 
B) the velocity of the bus is backward. 
C) You cannot conclude anything about the direction of the velocity of the bus.

Question 14

Suppose the force of the air drag on an object is proportional to the speed of the object and in the direction opposite the object's velocity.If you throw an object upward,the magnitude of its acceleration is greatest

Accepted Answer

A) right after the object is released. 
B) at the top of its trajectory. 
C) The acceleration of the object is the same throughout the entire trajectory. 
A) right after the object is released. 
B) at the top of its trajectory. 
C) The acceleration of the object is the same throughout the entire trajectory.

Question 15

A 615 N student standing on a scale in an elevator notices that the scale reads 645 N.From this information,the student knows that the elevator must be moving

Accepted Answer

A) downward. 
B) upward. 
C) You cannot tell if it is moving upward or downward. 
A) downward. 
B) upward. 
C) You cannot tell if it is moving upward or downward.

Question 16

Which one of the following free-body diagrams best represents the free-body diagram,with correct relative force magnitudes,of a person in an elevator that is traveling upward but is gradually slowing down at a rate of 9 m/s2?   f is the force of the floor on the person and   g is the force of gravity on the person.

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 17

A crate is sliding down an inclined ramp at a constant speed of 0.55 m/s.The vector sum of all the forces acting on this crate must point down the ramp.

Accepted Answer

A) True 
 B)False

Question 18

The graph in the figure shows the x component of the acceleration of a 2.4-kg object as a function of time (in ms).   (a)At what time(s)does the x component of the net force on the object reach its maximum magnitude,and what is that maximum magnitude?
(b)What is the x component of the net force on the object at time t = 0.0 ms and at t = 4.0 ms?

Accepted Answer

(a)At 3.0

Question 19

A stalled car is being pushed up a hill at constant velocity by three people.The net force on the car is

Accepted Answer

A) zero. 
B) up the hill and equal to the weight of the car. 
C) down the hill and equal to the weight of the car. 
D) up the hill and greater than the weight of the car. 
E) down the hill and greater than the weight of the car. 
A) zero. 
B) up the hill and equal to the weight of the car. 
C) down the hill and equal to the weight of the car. 
D) up the hill and greater than the weight of the car. 
E) down the hill and greater than the weight of the car.

Question 20

A dog is standing in the bed of a pickup truck.The bed is coated with ice,causing the force of friction between the dog and the truck to be zero.The truck is initially at rest,and then accelerates to the right,moving along a flat road.As seen from a stationary observer (watching the truck move to the right),the dog

Accepted Answer

A) does not move left or right,but the back of the truck moves towards the dog. 
B) moves to the right,but not as quickly as the truck is moving to the right,causing it to slide towards the back of the truck. 
C) moves to the right at the same rate as the truck,so it doesn't slide. 
D) moves to the left,as the truck moves to the right,causing the dog to slide towards the back of the truck. 
A) does not move left or right,but the back of the truck moves towards the dog. 
B) moves to the right,but not as quickly as the truck is moving to the right,causing it to slide towards the back of the truck. 
C) moves to the right at the same rate as the truck,so it doesn't slide. 
D) moves to the left,as the truck moves to the right,causing the dog to slide towards the back of the truck.

Exam 5: Force and Motion

An 1100-kg car traveling at 27.0 m/s starts to slow down and comes to a complete stop in 578 m.What is the magnitude of the average braking force acting on the car?

A child on a sled starts from rest at the top of a 15° slope.If the trip to the bottom takes how long is the slope? Assume that frictional forces may be neglected.

On its own,a certain tow-truck has a maximum acceleration of 3.0 m/s2.What would be the maximum acceleration when this truck was towing a bus of twice its own mass?

Two forces act on a object.One force has magnitude 65 N directed 59° clockwise from the positive x-axis,and the other has a magnitude 35 N at 32° clockwise from the positive y-axis.What is the magnitude of this object's acceleration?

Suppose you are playing hockey on a new-age ice surface for which there is no friction between the ice and the hockey puck.You wind up and hit the puck as hard as you can.After the puck loses contact with your stick,the puck will

An object is moving forward with a constant velocity.Which statement about this object MUST be true?

The figure shows two forces acting on an object,with magnitudes and What third force will cause the object to be in equilibrium (acceleration equals zero)?

Which one of the following free-body diagrams best represents the free-body diagram,with correct relative force magnitudes,of a person in an elevator that is traveling upward with an unchanging velocity? f is the force of the floor on the person and g is the force of gravity on the person.

You are standing in a moving bus,facing forward,and you suddenly fall forward as the bus comes to an immediate stop.The force acting on you that causes you to fall forward is

An object is moving to the right,and experiencing a net force that is directed to the right.The magnitude of the force is decreasing with time.The speed of the object is

If a 5.0 kg box is pulled simultaneously by a 10.0 N force and a 5.0 N force,then its acceleration must be

The figure shows an acceleration-versus-force graph for three objects pulled by rubber bands.The mass of object 2 is 36 kg.What are the masses of objects 1 and 3?

You are seated in a bus and notice that a hand strap that is hanging from the ceiling hangs away from the vertical in the backward direction.From this observation,you can conclude that

Suppose the force of the air drag on an object is proportional to the speed of the object and in the direction opposite the object's velocity.If you throw an object upward,the magnitude of its acceleration is greatest

A 615 N student standing on a scale in an elevator notices that the scale reads 645 N.From this information,the student knows that the elevator must be moving

A crate is sliding down an inclined ramp at a constant speed of 0.55 m/s.The vector sum of all the forces acting on this crate must point down the ramp.

A stalled car is being pushed up a hill at constant velocity by three people.The net force on the car is

Concepts of Motion

Kinematics in One Dimension

Vectors and Coordinate Systems

Kinematics in Two Dimensions

Dynamics I: Motion Along a Line

Newtons Third Law

Dynamics II: Motion in a Plane

Work and Kinetic Energy

Interactions and Potential Energy

Impulse and Momentum

Rotation of a Rigid Body

Newtons Theory of Gravity

Fluids and Elasticity

Oscillations

Traveling Waves

Superposition

A Macroscopic Description of Matter

Work, heat, and the First Law of Thermodynamics

The Micromacro Connection

Heat Engines and Refrigerators

Electric Charges and Forces

The Electric Field

Gausss Law

The Electric Potential

Potential and Field

Current and Resistance

Fundamentals of Circuits

The Magnetic Field

Electromagnetic Induction

Electromagnetic Fields and Waves

Ac Circuits

Wave Optics

Ray Optics

Optical Instruments

Relativity

The Foundations of Modern Physics

Quantization

Wave Functions and Uncertainty

One-Dimensional Quantum Mechanics

Atomic Physics

Nuclear Physics

Filters

On its own,a certain tow-truck has a maximum acceleration of 3.0 m/s².What would be the maximum acceleration when this truck was towing a bus of twice its own mass?

Which one of the following free-body diagrams best represents the free-body diagram,with correct relative force magnitudes,of a person in an elevator that is traveling upward with an unchanging velocity? _f is the force of the floor on the person and _g is the force of gravity on the person.