Energy

An object that has kinetic energy must be

• lifted above Earth’s surface

• at rest

•  in motion

• changing direction

 In the diagram to the right, a roller coaster car starts from rest and moves along the track. At which point does the roller coaster car have the greatest potential energy? 

• A

• B

• C

• D

The ____ energy of an object depends on both the height and the mass of an object.

•  radiant

• chemical

• kinetic

• gravitational potential

When an object is dropped what happens to potential and kinetic energy as it falls?

• GPE goes up, KE goes down

• GPE goes down, KE goes down

• GPE goes up, KE goes up

• GPE goes down, KE goes up

The picture to the right shows a person swinging a baseball bat, starting at point A.  The kinetic energy of the bat would be the greatest at

• Point A

• Point C

• Point B

• Point D

A 5 kg medicine ball is thrown upward at a speed of 2 m/s. How much energy does it have?

• 5 J

• 10 J        

• 20 J        

•   98 J

An object has a velocity of 9 m/s and a mass of 20 kg.  What is the kinetic energy of the object?

•  90 J

• 810 J

• 180 J

• 1,620 J

The law of ____ states that energy in a system can change forms but can never be created or destroyed.

•  conservation of energy

• conversion of energy

• consecration of energy

• construction of energy

When a ball is dropped it bounces until it eventually stops.  Why does this happen?

•  Some of the ball’s energy is lost.

• Some of the ball’s energy is converted to other forms, such as thermal and sound.

• All of the ball’s energy is eventually converted to potential energy when the ball stops bouncing.

•  All of the ball’s energy is eventually converted to kinetic energy when the ball stops bouncing.

An example of an energy conversion from kinetic to thermal energy would be

• friction

• flower

• television

• gravity