Power

Power

Multiple Choice

How much power is required to raise a 200-kg crate a vertical distance of 2 m in a time of 4 s?

• 400 W

• 1000 W

• 1600 W

• 4000 W

Multiple Choice

Which requires more work – a person walking up stairs or a person running up stairs?

• walking

• running

• they require equal work

• no work is required for either because the movement is vertical

Multiple Choice

Which requires more power – a person walking up stairs or a person running up stairs?

• walking

• running

• they require equal power output

• no power is required at all

Multiple Choice

A major league pitcher can throw a baseball with a kinetic energy of 150 J. How much work must the pitcher do to the ball to give it that much KE?

• 150 J

• 0

• Can’t tell without knowing the mass of the ball

Multiple Choice

You are traveling along a freeway at 65 mi/h; your car has kinetic energy. You suddenly skid to a stop because of congested traffic. What happened to the kinetic energy your car just had?

• It is all in internal energy in the road

• It is all in internal energy in the tires

• Some of it has transformed to internal energy for the tires and the road, and some of it transferred away by sound energy and thermal energy into the air.

• It was destroyed

Multiple Choice

Four students run up the stairs in the time shown. Which student has the largest power output?

• A

• B

• C

• D

Multiple Choice

If you have the same work as someone, but in less time

• You are more powerful

• You are less powerful

• You have the same power

Multiple Choice

Person A and Person B are both using the same amount of work to lift something. Person A takes half as much time to do it. Who has greater power.

• Person A

• Person B