Work, Energy and Power - grade 9

Unit for work done is

• Newton

• Joule

• meter

• second

What is the formula for work?

• Force = work x distance
• Distance = force x work
• Work = force x displacement

• Work = force x mass

The equation for Power is

• power = mass x time

• power = work / time

• power = time / work

• power = work x time

_______________ is done when a force acts on an object and the object moves in the direction of the force.

• Work

• Kinetic energy

• Watt

• Joule

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

What is the formula for Gravitational Potential Energy?

• PE = m*g*h
• KE = 1/2m*v2
• W = F*d
• P = W/t

What is the formula for Kinetic Energy?

• PE = m*g*h
• KE = 1/2m*v2
• W = F*d
• P = W/t