Question 1

If a spaceship 100 m long when at rest on the earth were to travel at nine-tenths the speed of light, its length as measured by an observer on the earth would be

Accepted Answer

A) 0. 
B) less than 100 m. 
C) 100 m. 
D) more than 100 m. 
A) 0. 
B) less than 100 m. 
C) 100 m. 
D) more than 100 m.

Question 2

The height above the ground of a child on a swing varies from 0.5 m at the lowest point to 2.0 m at the highest point.The maximum speed of the child is

Accepted Answer

A) about 5.4 m/s. 
B) about 7.7 m/s. 
C) about 29.4 m/s. 
D) dependent on the child's mass. 
A) about 5.4 m/s. 
B) about 7.7 m/s. 
C) about 29.4 m/s. 
D) dependent on the child's mass.

Question 3

A 1-kg object is moving at 10 m/s.To double its kinetic energy, its speed should be increased to approximately

Accepted Answer

A) 14 m/s. 
B) 15 m/s. 
C) 20 m/s. 
D) 40 m/s. 
A) 14 m/s. 
B) 15 m/s. 
C) 20 m/s. 
D) 40 m/s.

Question 4

To prevent it from tumbling in flight, a projectile such as a football is sent off spinning.The physical principle involved is

Accepted Answer

A) conservation of energy. 
B) conservation of linear momentum. 
C) conservation of angular momentum. 
D) the first law of motion. 
A) conservation of energy. 
B) conservation of linear momentum. 
C) conservation of angular momentum. 
D) the first law of motion.

Question 5

A 2-kg book is held 1 m above the floor for 50 s.The work done is

Accepted Answer

A) 0. 
B) 10.2 J. 
C) 100 J. 
D) 980 J. 
A) 0. 
B) 10.2 J. 
C) 100 J. 
D) 980 J.

Question 6

A 1-kg mass has a KE of 1 J when its speed is

Accepted Answer

A) 0.45 m/s. 
B) 1 m/s. 
C) 1.4 m/s. 
D) 4.4 m/s. 
A) 0.45 m/s. 
B) 1 m/s. 
C) 1.4 m/s. 
D) 4.4 m/s.

Question 7

The work done in lifting 30 kg of bricks to a height of 20 m on a building under construction is

Accepted Answer

A) 61 J. 
B) 600 J. 
C) 2940 J. 
D) 5880 J. 
A) 61 J. 
B) 600 J. 
C) 2940 J. 
D) 5880 J.

Question 8

When the momentum of a moving object is increased, there must also be an increase in which one or more of the following of the object's properties?

Accepted Answer

A) speed 
B) acceleration 
C) kinetic energy 
D) potential energy 
E) Both A and C 
A) speed 
B) acceleration 
C) kinetic energy 
D) potential energy 
E) Both A and C

Question 9

The upper limit to the speed of an object with mass

Accepted Answer

A) depends on the mass. 
B) corresponds to a KE equal to its rest energy. 
C) is the speed of sound. 
D) is the speed of light. 
A) depends on the mass. 
B) corresponds to a KE equal to its rest energy. 
C) is the speed of sound. 
D) is the speed of light.

Question 10

A bowling ball rolling on level ground at the speed v strikes a basketball at rest.The basketball moves off in the original direction of the bowling ball

Accepted Answer

A) with the speed v while the bowling ball stops. 
B) faster than v while the bowling ball continues slower than v. 
C) with the speed v while the bowling ball moves backward. 
D) together with the bowling ball at the same speed of less than v. 
A) with the speed v while the bowling ball stops. 
B) faster than v while the bowling ball continues slower than v. 
C) with the speed v while the bowling ball moves backward. 
D) together with the bowling ball at the same speed of less than v.

Question 11

The mass equivalent of 6.0 MJ is

Accepted Answer

A) 6.7 * 10-11 kg. 
B) 5.4 * 10-9 kg. 
C) 6.7 * 10-3 kg. 
D) 2.0 * 10-2 kg. 
A) 6.7 * 10-11 kg. 
B) 5.4 * 10-9 kg. 
C) 6.7 * 10-3 kg. 
D) 2.0 * 10-2 kg.

Question 12

A 40-kg boy climbs a vertical ladder at 0.5 m/s.His power output is

Accepted Answer

A) 5 W. 
B) 14 W. 
C) 20 W. 
D) 196 W. 
A) 5 W. 
B) 14 W. 
C) 20 W. 
D) 196 W.

Question 13

What never changes when two or more objects collide is

Accepted Answer

A) the momentum of each object. 
B) the kinetic energy of each object. 
C) the total momentum of all the objects. 
D) the total kinetic energy of all the objects. 
A) the momentum of each object. 
B) the kinetic energy of each object. 
C) the total momentum of all the objects. 
D) the total kinetic energy of all the objects.

Question 14

An 800-kg car moving at 80 km/h collides head-on with a 1200-kg car moving at 40 km/h in the opposite direction.If they stick together, the wreckage now has an initial speed of

Accepted Answer

A) 8 km/h. 
B) 40 km/h. 
C) 56 km/h. 
D) 60 km/h. 
A) 8 km/h. 
B) 40 km/h. 
C) 56 km/h. 
D) 60 km/h.

Question 15

A ball whose momentum is mv strikes a wall and bounces off.The change in the ball's momentum is

Accepted Answer

A) 0. 
B) 0.5 mv 
C) mv 
D) 2 mv 
A) 0. 
B) 0.5 mv 
C) mv 
D) 2 mv

Question 16

A 1000-kg car whose speed is 80 km/h (22.2 m/s) has a kinetic energy of

Accepted Answer

A) 25.2 kJ. 
B) 247 kJ. 
C) 2.42 MJ. 
D) 3.2 MJ. 
A) 25.2 kJ. 
B) 247 kJ. 
C) 2.42 MJ. 
D) 3.2 MJ.

Question 17

In bright sunlight, a solar cell with an efficiency of 20% might have a power output per square meter of

Accepted Answer

A) 2 W. 
B) 20 W. 
C) 200 W. 
D) 2000 W. 
A) 2 W. 
B) 20 W. 
C) 200 W. 
D) 2000 W.

Question 18

When a ton of coal burns, it loses 3.3 * 10-7 kg of mass.The energy given off is

Accepted Answer

A) 3.7 * 10-24 J. 
B) 3.3 * 10-7 J. 
C) 100 J. 
D) 3.0 * 1010 J. 
A) 3.7 * 10-24 J. 
B) 3.3 * 10-7 J. 
C) 100 J. 
D) 3.0 * 1010 J.

Question 19

Which of the following quantities is always the same to all observers?

Accepted Answer

A) time intervals 
B) the speed of an object 
C) the speed of sound 
D) the speed of light 
A) time intervals 
B) the speed of an object 
C) the speed of sound 
D) the speed of light

Question 20

A sedentary person requires about 6 million J of energy per day.This rate of energy consumption is equivalent to about

Accepted Answer

A) 70 W. 
B) 335 W. 
C) 600 W. 
D) 250,000 W. 
A) 70 W. 
B) 335 W. 
C) 600 W. 
D) 250,000 W.

If a spaceship 100 m long when at rest on the earth were to travel at nine-tenths the speed of light, its length as measured by an observer on the earth would be

The height above the ground of a child on a swing varies from 0.5 m at the lowest point to 2.0 m at the highest point.The maximum speed of the child is

A 1-kg object is moving at 10 m/s.To double its kinetic energy, its speed should be increased to approximately

To prevent it from tumbling in flight, a projectile such as a football is sent off spinning.The physical principle involved is

A 2-kg book is held 1 m above the floor for 50 s.The work done is

A 1-kg mass has a KE of 1 J when its speed is

The work done in lifting 30 kg of bricks to a height of 20 m on a building under construction is

When the momentum of a moving object is increased, there must also be an increase in which one or more of the following of the object's properties?

The upper limit to the speed of an object with mass

A bowling ball rolling on level ground at the speed v strikes a basketball at rest.The basketball moves off in the original direction of the bowling ball

The mass equivalent of 6.0 MJ is

A 40-kg boy climbs a vertical ladder at 0.5 m/s.His power output is

What never changes when two or more objects collide is

An 800-kg car moving at 80 km/h collides head-on with a 1200-kg car moving at 40 km/h in the opposite direction.If they stick together, the wreckage now has an initial speed of

A ball whose momentum is mv strikes a wall and bounces off.The change in the ball's momentum is

A 1000-kg car whose speed is 80 km/h (22.2 m/s) has a kinetic energy of

In bright sunlight, a solar cell with an efficiency of 20% might have a power output per square meter of

When a ton of coal burns, it loses 3.3 * 10^-7 kg of mass.The energy given off is

Which of the following quantities is always the same to all observers?

A sedentary person requires about 6 million J of energy per day.This rate of energy consumption is equivalent to about

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Exam 3: Energy

If a spaceship 100 m long when at rest on the earth were to travel at nine-tenths the speed of light, its length as measured by an observer on the earth would be

The height above the ground of a child on a swing varies from 0.5 m at the lowest point to 2.0 m at the highest point.The maximum speed of the child is

A 1-kg object is moving at 10 m/s.To double its kinetic energy, its speed should be increased to approximately

To prevent it from tumbling in flight, a projectile such as a football is sent off spinning.The physical principle involved is

A 2-kg book is held 1 m above the floor for 50 s.The work done is

A 1-kg mass has a KE of 1 J when its speed is

The work done in lifting 30 kg of bricks to a height of 20 m on a building under construction is

When the momentum of a moving object is increased, there must also be an increase in which one or more of the following of the object's properties?

The upper limit to the speed of an object with mass

A bowling ball rolling on level ground at the speed v strikes a basketball at rest.The basketball moves off in the original direction of the bowling ball

The mass equivalent of 6.0 MJ is

A 40-kg boy climbs a vertical ladder at 0.5 m/s.His power output is

What never changes when two or more objects collide is

An 800-kg car moving at 80 km/h collides head-on with a 1200-kg car moving at 40 km/h in the opposite direction.If they stick together, the wreckage now has an initial speed of

A ball whose momentum is mv strikes a wall and bounces off.The change in the ball's momentum is

A 1000-kg car whose speed is 80 km/h (22.2 m/s) has a kinetic energy of

In bright sunlight, a solar cell with an efficiency of 20% might have a power output per square meter of

When a ton of coal burns, it loses 3.3 * 10-7 kg of mass.The energy given off is

Which of the following quantities is always the same to all observers?

A sedentary person requires about 6 million J of energy per day.This rate of energy consumption is equivalent to about

The Scientific Method

Motion

Energy and the Future

Matter and Heat

Electricity and Magnetism

Waves

The Nucleus

The Atom

The Periodic Law

Crystals, Ions, and Solutions

Chemical Reactions

Organic Chemistry

Atmosphere and Hydrosphere

The Rock Cycle

The Evolving Earth

The Solar System

The Stars

Universe

Filters

When a ton of coal burns, it loses 3.3 * 10^-7 kg of mass.The energy given off is