Work and Power Practice

The SI Unit for Time

• Newton (N)
• Joule (J)
• Second (s)
• Watt (W)

The SI Unit for Power

• Newton (N)
• Joule (J)
• Second (s)
• Watt (W)

The SI Unit for Work

• Newton (N)
• Joule (J)
• Second (s)
• Watt (W)

What is the formula for Power?

• E=mc²

• W= F x d

• P = W/t

What is the formula for Work?

• E=mc²

• W= F x d

• P = W/t

W = 500 Joules 
t = 25 seconds
P = ???

• 0.05 W
• 20 W
• 12500 W
• 2000 W

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

• 30 watts

• 3 watts

• 120 watts

• 270 watts

While rowing across the lake during a race, John does 3960 J of work on the oars in 60 seconds. What is his power output?

• 56W

• 100W

• 66W

• None of the answers are correct

A mountain climber with a force of 90 N scales a 100 m cliff. How much work is done by the mountain climber?

• 1.11 W

• 90,000 J

• 0.9 J

• 9 W

A horse performs 15,000 joules of work pulling a wagon for 20 seconds. What is the horse's power?

• 750 W

• 300 W

• 2.25 J