Energy Test Review - Physical Science

Which of the following is a true statement about work?

• It measures how quickly an object accelerates 

• It measures how much effort is applied over a certain distance

• It measures the change in an object's rate of speed

• It measures how much time it takes to move a massive object

A kid applies a force of 70 N to a ball over 1.1 meters. How much work did he do on the ball? 

• 77 J

• 7.7 J 

• 0.7 J 

• 770 J 

A weightlifter lifts two 300 newton weights 1.5 meters off the ground. How much work has he done?

• 600 J 

• 660 J

• 900 J 

• 1200 J 

Simple machines make work easier by increasing what?

• The distance over which work is done 

• The force needed to do work 

• The time required to do work

• The acceleration of a massive object 

You do 90 joules of work in 30 seconds. How much power have you generated?

• 30 watts

• 3 watts

• 120 watts

• 270 watts

The unit of work is the ...

• joule

• force

The unit of power is the...

• work

• watt

Work is done on an object when the object moves in the SAME direction in which the force is applied.

• True

• False

Power is the RATE at which work is done. 

• True

• False

Potential energy is __________ energy. 

• motion 

• moving

• slow

• stored