Work, Energy, and Power Review

Which of the following is a unit for energy?

• Meters

• Newtons

• Joules

• Watts

Which of the following statements best describes the law of conservation of energy?

• Energy can be created but not destroyed.

• Energy can be destroyed but not created.

• Energy cannot be created or destroyed.

• Energy can be created and destroyed freely.

A rock is thrown up into the air. What type of energy does it have as it is being thrown?

• Gravitational potential energy

• Kinetic energy

• Elastic potential energy

• Thermal energy

A rock is thrown up into the air. What type of energy does it have at its maximum height?

• Gravitational potential energy

• Kinetic energy

• Elastic potential energy

• Thermal energy

You apply a 25 N force to a crate causing it to displace by 5 meters. How much work is done?

• 5 J

• 30 J

• 20 J

• 125 J

You apply a 25 N force to a crate causing it to displace by 5 meters., it takes 4 seconds to push the crate across the room. What average power was generated?

• 125 W

• 31.25 W

• 500 W

• Not enough information is provided.

You pull a backpack across the room with a force of 30 N at an angle of 25°. How much work is created if you pull the backpack for 12 m? (Round to the nearest whole number)

• 360 J

• 750 J

• 300 J

• 326 J

You lift a 2 kg book off the ground by 3 meters. How much gravitational potential energy is stored in the book?

• 6 J

• 58.8 J

• 19.6 J

• 29.4 J

A 3 kg ball rolls across the floor at 2 m/s, how much kinetic energy does it have?

• 6 J

• 12 J

• 3 J

• Not enough information is provided.

A 500 kg roller coaster car moves at 10 m/s while it is 20 m in the air. What type(s) of energy does the car have?

• Kinetic energy

• Gravitational potential energy

• Spring potential energy

• a and b