Question

A block of weight w = 25.0 N sits on a frictionless inclined plane, which makes an angle θ = 20.0 ∘ with respect to the horizontal, as shown in the figure. (Figure 1)A force of magnitude F = 8.55 N , applied parallel to the incline, is just sufficient to pull the block up the plane at constant speed.

Part B

What is Wg, the work done on the block by the force of gravity w⃗  as the block moves a distance L = 5.00 m up the incline?

Express your answer numerically in joules.

Part C

What is WF, the work done on the block by the applied force F⃗  as the block moves a distance L = 5.00 m up the incline?

Express your answer numerically in joules.

Part D

What is WN, the work done on the block by the normal force as the block moves a distance L = 5.00 m up the inclined plane?

Express your answer numerically in joules.

Answer 1

a) Work done by gravity

the angle between gravity force and displacement is

b) Work done by applied force is

the angle between applied force and displacement is 0

W = 42.75 J

c) Work done by the normal force

The angle between the normal force and the displacement is 90

W = 0