Question

10. How much total work do you do when you lift a 50 kg microwave 1.0 m off the ground and then push it 1.0 m

across a counter with a force of 50 N?

Answer 1

Work formula:

`W = Fd\cos(\theta)`

F = 50N, d = 1.0 m

When you lift something straight up, the angle of the force is 90º

cos(90º) is 0, so there's no work done when you lift the microwave off the ground

`W = (50N)(1.0)(0) = 0`

F = 50N, d = 1.0 m

When you push the microwave, the angle is 0º and cos(0º) is 1. So there is work done here:

`W = (50 N)(1.0m)(1)`

`W = 50`

total work = 50 joules