Work Power Energy

Energy is

• how fast you do something.

• the ability to do work.

• confusing.

• how fast you lift something.

If you use 30 J of energy to move an object, you have done ____ J of work.

• 3

• 10

• 30

• 0

Jane carries a 5 kg box and Lorie carries a 10 kg box up a set of stairs, who did more work?

• Jane because his box was lighter.

• Lorie because her box weighed more.

• Can't tell.

How much power is generated by Ashley (50 kg) running up a 6 m flight of stairs in 5 seconds?

• 60 W

• 62 W

• 600 W

• 1500 W

If you carry a 5 kg box across the room at a constant velocity

• you do no work.

• you do some work.

• you do negative work.

• Cannot be determined.

If you run up the stairs slower you will

• do more work.

• do less work.

• generate more power.

• generate less power.

What is the kinetic energy of a 10 kg ball moving at 3 m/s?

• 15 J

• 30 J

• 45 J

• 90 J

A 5 kg cat falls off a 3 m tall fridge. What is the cat's PE as it starts to fall?

• 15 J

• 30 J

• 150 J

• 1470 J

A 5 kg cat falls off a 3 m tall fridge. What is the cat's KE just before it lands on the floor?

• 15 J

• 30 J

• 150 J

• 1470 J

What is the mass of an object with 1200 J of PE when it is 5 meters above the ground?

• 10 kg

• 24 kg

• 100 kg

• 240 kg