Question 1

If a charging rhinoceros has momentum, it must also have

Accepted Answer

A) potential energy. 
B) kinetic energy. 
C) work. 
D) all of the above 
A) potential energy. 
B) kinetic energy. 
C) work. 
D) all of the above

Question 2

Recoil is noticeable if we throw a heavy ball while standing on a skateboard. If instead we go through the throwing motion but hold onto the ball, without friction effects our net recoil will be

Accepted Answer

A) zero. 
B) the same as before. 
C) small, but noticeable. 
A) zero. 
B) the same as before. 
C) small, but noticeable.

Question 3

A 1-kg ball dropped from a height of 2 m rebounds only 1.5 m after hitting the ground. The amount of energy converted to heat is about

Accepted Answer

A) 0.5 J. 
B) 1.0 J. 
C) 1.5 J. 
D) 2.0 J. 
E) more than 2.0 J. 
A) 0.5 J. 
B) 1.0 J. 
C) 1.5 J. 
D) 2.0 J. 
E) more than 2.0 J.

Question 4

The force of a falling apple hitting the ground depends upon

Accepted Answer

A) the speed of the apple just before it hits. 
B) the time of contact with the ground. 
C) whether or not the apple bounces. 
D) all of the above 
A) the speed of the apple just before it hits. 
B) the time of contact with the ground. 
C) whether or not the apple bounces. 
D) all of the above

Question 5

A sandbag in outer space moves at 3 m/s when it collides and sticks to a half-as-massive sandbag initially at rest. Compared with the kinetic energy of the moving sandbag before collision, the kinetic energy of the coupled sandbags after collision is

Accepted Answer

A) one-third. 
B) two-thirds. 
C) three-quarters. 
D) not enough information 
A) one-third. 
B) two-thirds. 
C) three-quarters. 
D) not enough information

Question 6

A diesel locomotive coasting at 10 km/h runs into a stationary flatcar. The locomotive weighs four times as much as the flatcar. How fast do the locomotive and flatcar move when they stick together upon collision?

Accepted Answer

Momentum before collision = mo

Question 7

A diver who weighs 500 N steps off a diving board 10 m above the water hits the water with kinetic energy of

Accepted Answer

A) 10 J. 
B) 500 J. 
C) 510 J. 
D) 5000 J. 
E) more than 5000 J. 
A) 10 J. 
B) 500 J. 
C) 510 J. 
D) 5000 J. 
E) more than 5000 J.

Question 8

Discuss how energy conservation applies to a swinging pendulum. Where is potential energy the most? The least? Where is kinetic energy the most? The least? Where is the pendulum bob moving fastest? Slowest?

Accepted Answer

The swinging pendulum has the most gravi

Question 9

When an apple falls to the ground, momentum is transferred to the ground. The momentum absorbed by the ground is

Accepted Answer

A) negligible compared to the momentum of the apple. 
B) greater than that of the apple if the apple bounces. 
C) greater than that of the apple in all cases. 
D) none of the above 
A) negligible compared to the momentum of the apple. 
B) greater than that of the apple if the apple bounces. 
C) greater than that of the apple in all cases. 
D) none of the above

Question 10

Suppose an astronaut in outer space plays a solitary game of "throw, bounce, and catch" by tossing a ball against a very massive and perfectly elastic concrete wall.

Accepted Answer

A) The astronaut will catch the ball on one bounce only. 
B) The astronaut will never catch the first bounce. 
C) The astronaut's time between catches will decrease as the game progresses. 
D) none of the above 
A) The astronaut will catch the ball on one bounce only. 
B) The astronaut will never catch the first bounce. 
C) The astronaut's time between catches will decrease as the game progresses. 
D) none of the above

Question 11

Lifting a 100-N load with 50 N of force lifts it

Accepted Answer

A) half as high. 
B) as high. 
C) twice as high 
A) half as high. 
B) as high. 
C) twice as high

Question 12

A 1-kg glider and a 2-kg glider both slide toward each other at 1 m/s on an air track. They collide and stick. The combined gliders move at

Accepted Answer

A) 0 m/s. 
B) 1/2 m/s. 
C) 1/3 m/s. 
D) 1/6 m/s. 
E) 1.5 m/s. 
A) 0 m/s. 
B) 1/2 m/s. 
C) 1/3 m/s. 
D) 1/6 m/s. 
E) 1.5 m/s.

Question 13

A 1000-kg car moving at 10 m/s that brakes to a stop in 5 s has an average braking force of

Accepted Answer

A) 1000 N. 
B) 2000 N. 
C) 3000 N. 
D) 4000 N. 
E) 5000 N. 
A) 1000 N. 
B) 2000 N. 
C) 3000 N. 
D) 4000 N. 
E) 5000 N.

Question 14

Can an object have mechanical energy without having momentum? Momentum without having mechanical energy? Explain.

Accepted Answer

An object can have potential energy with

Question 15

The speed of a bullet fired from a gun will be about the same as the speed of the recoiling gun

Accepted Answer

A) when momentum is conserved. 
B) because velocity is conserved. 
C) when both velocity and momentum are conserved. 
D) if the masses of the bullet and gun are equal. 
E) none of the above 
A) when momentum is conserved. 
B) because velocity is conserved. 
C) when both velocity and momentum are conserved. 
D) if the masses of the bullet and gun are equal. 
E) none of the above

Question 16

A person on the edge of a roof throws a piece of tile downward that strikes the ground with 100 J of kinetic energy. Another identical tile is thrown upward with the same initial speed, and this too falls to the ground. Neglecting air resistance, the second tile hits the ground with a kinetic energy of

Accepted Answer

A) less than 100 J. 
B) 100 J. 
C) 200 J. 
D) more than 200 J. 
E) none of the above 
A) less than 100 J. 
B) 100 J. 
C) 200 J. 
D) more than 200 J. 
E) none of the above

Question 17

Which has greater kinetic energy, a car traveling at 30 km/h or another car of half the mass traveling at 60 km/h?

Accepted Answer

A) the 30-km/h car 
B) the 60-km/h car 
C) both have the same kinetic energy 
A) the 30-km/h car 
B) the 60-km/h car 
C) both have the same kinetic energy

Question 18

A cannonball fired from a long-barrel cannon will have a greater muzzle velocity because the cannonball receives a greater

Accepted Answer

A) force. 
B) impulse. 
C) both 
D) neither 
A) force. 
B) impulse. 
C) both 
D) neither

Question 19

When a non-hybrid car brakes to a stop its kinetic energy transforms to

Accepted Answer

A) stopping energy. 
B) potential energy. 
C) energy of motion. 
D) energy of rest. 
E) heat. 
A) stopping energy. 
B) potential energy. 
C) energy of motion. 
D) energy of rest. 
E) heat.

Question 20

A common car engine is 20% efficient. When cruising, the car encounters an average retarding force of 1000 N. If the energy content of gasoline is 40 MJ/L, how many kilometers per liter does the car achieve?

Accepted Answer

A) 14 km/L 
B) 12 km/L 
C) 10 km/L 
D) 8 km/L 
E) none of the above 
A) 14 km/L 
B) 12 km/L 
C) 10 km/L 
D) 8 km/L 
E) none of the above

Exam 3: Momentum and Energy

If a charging rhinoceros has momentum, it must also have

Recoil is noticeable if we throw a heavy ball while standing on a skateboard. If instead we go through the throwing motion but hold onto the ball, without friction effects our net recoil will be

A 1-kg ball dropped from a height of 2 m rebounds only 1.5 m after hitting the ground. The amount of energy converted to heat is about

The force of a falling apple hitting the ground depends upon

A sandbag in outer space moves at 3 m/s when it collides and sticks to a half-as-massive sandbag initially at rest. Compared with the kinetic energy of the moving sandbag before collision, the kinetic energy of the coupled sandbags after collision is

A diesel locomotive coasting at 10 km/h runs into a stationary flatcar. The locomotive weighs four times as much as the flatcar. How fast do the locomotive and flatcar move when they stick together upon collision?

A diver who weighs 500 N steps off a diving board 10 m above the water hits the water with kinetic energy of

Discuss how energy conservation applies to a swinging pendulum. Where is potential energy the most? The least? Where is kinetic energy the most? The least? Where is the pendulum bob moving fastest? Slowest?

When an apple falls to the ground, momentum is transferred to the ground. The momentum absorbed by the ground is

Suppose an astronaut in outer space plays a solitary game of "throw, bounce, and catch" by tossing a ball against a very massive and perfectly elastic concrete wall.

Lifting a 100-N load with 50 N of force lifts it

A 1-kg glider and a 2-kg glider both slide toward each other at 1 m/s on an air track. They collide and stick. The combined gliders move at

A 1000-kg car moving at 10 m/s that brakes to a stop in 5 s has an average braking force of

Can an object have mechanical energy without having momentum? Momentum without having mechanical energy? Explain.

The speed of a bullet fired from a gun will be about the same as the speed of the recoiling gun

Which has greater kinetic energy, a car traveling at 30 km/h or another car of half the mass traveling at 60 km/h?

A cannonball fired from a long-barrel cannon will have a greater muzzle velocity because the cannonball receives a greater

When a non-hybrid car brakes to a stop its kinetic energy transforms to

A common car engine is 20% efficient. When cruising, the car encounters an average retarding force of 1000 N. If the energy content of gasoline is 40 MJ/L, how many kilometers per liter does the car achieve?

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 Timereading 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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