Potential And Kinetic Energy Worksheet (Page 14 of 29) in pdf

Potential And Kinetic Energy Worksheet Page 14

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A motor does 5,000. joules of work in 20. seconds. What is the power of the motor?

A machine does 1,500 joules of work in 30. seconds. What is the power of this machine?

A hair dryer uses 72,000 joules of energy in 60. seconds. What is the power of this hair dryer?

A toaster oven uses 67,500 joules of energy in 45 seconds to toast a piece of bread. What is the power of the

oven?

A horse moves a sleigh 1.00 kilometer by applying a horizontal 2,000.-newton force on its harness for

45.0 minutes. What is the power of the horse? (Hint: Convert time to seconds.)

A wagon is pulled at a speed of 0.40 m/s by a horse exerting an 1,800-newton horizontal force. What is the

power of this horse?

Suppose a force of 100. newtons is used to push an object a distance of 5.0 meters in 15 seconds. Find the

work done and the power for this situation.

Emily’s vacuum cleaner has a power rating of 200. watts. If the vacuum cleaner does 360,000 joules of

work, how long did Emily spend vacuuming?

Nicholas spends 20.0 minutes ironing shirts with his 1,800-watt iron. How many joules of energy were used

by the iron? (Hint: convert time to seconds).

10. It take a clothes dryer 45 minutes to dry a load of towels. If the dryer uses 6,750,000 joules of energy to dry

the towels, what is the power rating of the machine?

11. A 1000-watt microwave oven takes 90 seconds to heat a bowl of soup. How many joules of energy does it

use?

12. A force of 100. newtons is used to move an object a distance of 15 meters with a power of 25 watts. Find the

work done and the time it takes to do the work.

13. If a small machine does 2,500 joules of work on an object to move it a distance of 100. meters in

10. seconds, what is the force needed to do the work? What is the power of the machine doing the work?

14. A machine uses a force of 200 newtons to do 20,000 joules of work in 20 seconds. Find the distance the

object moved and the power of the machine. (Hint: A joule is the same as a Newton-meter.)

15. A machine that uses 200. watts of power moves an object a distance of 15 meters in 25 seconds. Find the

force needed and the work done by this machine.

Potential And Kinetic Energy Worksheet Page 14