Question 1

A boxer punches a sheet of paper in midair from rest to a speed of 40 m/s in 0.05 s.If the mass of the paper is 0.01 kg,the force of the punch on the paper is

Accepted Answer

A) 0.08 N. 
B) 0.8 N. 
C) 8.0 N. 
D) 80 N. 
A) 0.08 N. 
B) 0.8 N. 
C) 8.0 N. 
D) 80 N.

Question 2

Why does the force of gravity do no work on a bowling ball rolling along a bowling lane? Look ahead to the next chapter and apply your explanation to satellite motion.

Accepted Answer

Work is done on an object only when a fo

Question 3

According to the impulse-momentum relationship Ft = change in mv,a falling baseball hits a player with a force F.The t in the equation is the time

Accepted Answer

A) the ball falls before hitting the player. 
B) of contact of the ball hitting the player. 
C) of reflex as the player responds to being hit. 
D) all of the above 
E) none of the above 
A) the ball falls before hitting the player. 
B) of contact of the ball hitting the player. 
C) of reflex as the player responds to being hit. 
D) all of the above 
E) none of the above

Question 4

The force that accelerates a rocket in outer space is exerted on the rocket by the

Accepted Answer

A) rocket's engine. 
B) rocket's wings. 
C) atmospheric pressure. 
D) exhaust gases. 
E) none of the above 
A) rocket's engine. 
B) rocket's wings. 
C) atmospheric pressure. 
D) exhaust gases. 
E) none of the above

Question 5

If you push for an hour against a stationary wall,you do no work

Accepted Answer

A) on the wall. 
B) at all. 
C) both of these 
D) none of the above 
A) on the wall. 
B) at all. 
C) both of these 
D) none of the above

Question 6

What is the mass of a ball moving at 3 m/s with a momentum of 48 kg∙m/s?

Accepted Answer

A) 4 kg 
B) 12 kg 
C) 16 kg 
D) 144 kg 
E) none of these 
A) 4 kg 
B) 12 kg 
C) 16 kg 
D) 144 kg 
E) none of these

Question 7

When you can't escape being hit by a fast-moving object,you'll suffer a smaller force if the collision time is

Accepted Answer

A) long. 
B) short. 
C) the same way either way 
A) long. 
B) short. 
C) the same way either way

Question 8

An object lifted 10 m gains a certain amount of potential energy.If it is lifted 20 m,its gain in potential energy is

Accepted Answer

A) less. 
B) the same. 
C) twice as much. 
D) four times as much. 
E) more than four times as much. 
A) less. 
B) the same. 
C) twice as much. 
D) four times as much. 
E) more than four times as much.

Question 9

Although perpetual motion is the natural order of things in the universe

Accepted Answer

A) it follows that machines can operate and do work by perpetual motion. 
B) no perpetual-motion device that multiplies energy exists. 
C) both of these are false statements 
A) it follows that machines can operate and do work by perpetual motion. 
B) no perpetual-motion device that multiplies energy exists. 
C) both of these are false statements

Question 10

When a simple machine multiplies force,it decreases

Accepted Answer

A) potential energy. 
B) distance moved. 
C) both of these 
D) none of the above 
A) potential energy. 
B) distance moved. 
C) both of these 
D) none of the above

Question 11

The power expended for a barbell raised 2.0 m in 2 s is

Accepted Answer

A) 1 W. 
B) 4 W. 
C) 8 W. 
D) not enough information 
A) 1 W. 
B) 4 W. 
C) 8 W. 
D) not enough information

Question 12

Padded dashboards in cars are safer in an accident than non-padded ones because a person hitting the dash has

Accepted Answer

A) increased time of contact. 
B) decreased contact force. 
C) both of these 
D) neither of these 
A) increased time of contact. 
B) decreased contact force. 
C) both of these 
D) neither of these

Question 13

A 2-kg mass that weighs 20 N has 40 J of potential energy relative to the ground.What is its height?

Accepted Answer

A) 1 m 
B) 2 m 
C) 3 m 
D) 4 m 
E) none of the above 
A) 1 m 
B) 2 m 
C) 3 m 
D) 4 m 
E) none of the above

Question 14

When a 100-kg astronaut ejects 0.1 kg of gas at a speed of 50 m/s from her propulsion pistol,her recoil speed is

Accepted Answer

A) 50 m/s. 
B) 5.0 m/s. 
C) 0.5 m/s. 
D) 0.05 m/s. 
A) 50 m/s. 
B) 5.0 m/s. 
C) 0.5 m/s. 
D) 0.05 m/s.

Question 15

When you push an object a certain distance while applying twice the force,you do

Accepted Answer

A) twice as much work. 
B) four times as much work. 
C) the same amount of work. 
A) twice as much work. 
B) four times as much work. 
C) the same amount of work.

Question 16

Which has the greater momentum when moving?

Accepted Answer

A) a container ship 
B) a bullet 
C) either of these depending on speed 
A) a container ship 
B) a bullet 
C) either of these depending on speed

Question 17

An object that has kinetic energy must be

Accepted Answer

A) moving. 
B) falling. 
C) at an elevated position. 
D) at rest. 
E) none of the above 
A) moving. 
B) falling. 
C) at an elevated position. 
D) at rest. 
E) none of the above

Question 18

The fuel most likely to power tomorrow's scooters,forklifts,and busses is

Accepted Answer

A) hydrogen. 
B) helium. 
C) lithium. 
A) hydrogen. 
B) helium. 
C) lithium.

Question 19

Which of these is not a form of solar energy?

Accepted Answer

A) wind energy 
B) fossil fuel energy 
C) geothermal energy 
D) hydroelectric power 
A) wind energy 
B) fossil fuel energy 
C) geothermal energy 
D) hydroelectric power

Question 20

At the edge of a cliff you throw one ball downward and another ball upward at the same speed.Which will hit the ground faster? Does direction of the thrown ball make a difference? Explain.

Accepted Answer

According to the conservation of energy,

Exam 3: Momentum and Energy

A boxer punches a sheet of paper in midair from rest to a speed of 40 m/s in 0.05 s.If the mass of the paper is 0.01 kg,the force of the punch on the paper is

Why does the force of gravity do no work on a bowling ball rolling along a bowling lane? Look ahead to the next chapter and apply your explanation to satellite motion.

According to the impulse-momentum relationship Ft = change in mv,a falling baseball hits a player with a force F.The t in the equation is the time

The force that accelerates a rocket in outer space is exerted on the rocket by the

If you push for an hour against a stationary wall,you do no work

What is the mass of a ball moving at 3 m/s with a momentum of 48 kg∙m/s?

When you can't escape being hit by a fast-moving object,you'll suffer a smaller force if the collision time is

An object lifted 10 m gains a certain amount of potential energy.If it is lifted 20 m,its gain in potential energy is

Although perpetual motion is the natural order of things in the universe

When a simple machine multiplies force,it decreases

The power expended for a barbell raised 2.0 m in 2 s is

Padded dashboards in cars are safer in an accident than non-padded ones because a person hitting the dash has

A 2-kg mass that weighs 20 N has 40 J of potential energy relative to the ground.What is its height?

When a 100-kg astronaut ejects 0.1 kg of gas at a speed of 50 m/s from her propulsion pistol,her recoil speed is

When you push an object a certain distance while applying twice the force,you do

Which has the greater momentum when moving?

An object that has kinetic energy must be

The fuel most likely to power tomorrow's scooters,forklifts,and busses is

Which of these is not a form of solar energy?

At the edge of a cliff you throw one ball downward and another ball upward at the same speed.Which will hit the ground faster? Does direction of the thrown ball make a difference? Explain.

Patterns of Motion and Equilibrium

Newtons Laws of Motion

Gravity, Projectiles, and Satellites

Fluid Mechanics

Thermal Energy and Thermodynamics

Heat Transfer and Change of Phase

Static and Current Electricity

Magnetism and Electromagnetic Induction

Waves and Sound

Light

Atoms and the Periodic Table

The Atomic Nucleus and Radioactivity

Elements of Chemistry

How Atoms Bond and Molecules Attract

Mixtures

How Chemicals React

Two Classes of Chemical Reactions

Organic Compounds

Rocks and Minerals

Plate Tectonics and Earths Interior

Shaping Earths Surface

Geologic Time - Reading the Rock Record

The Oceans, Atmosphere, and Climatic Effects

Driving Forces of Weather

The Solar System

Stars and Galaxies

The Structure of Space and Time

Prologue: The Nature of Science

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