Question

Question is about finding force etc.?

Answer 1

the value of FN = 30 / (cos 15)

Explanation:

the work done by the force

`W = FN . S = FN . S . Cos (15)` where

S is the displacement vector.

we do have info that during the displacement the motion was

uniform so no net force was acting along the path .

the forces opposing the motion were friction added to the force due to gravity along the path acting downward.

the work done against the force of resistance is 900 J and the work done against gravity is 2100 J.

therefore the total work done

`W= 3000 J = FN . S . Cos (15)`

therefore the force`FN = 30 /cos (15) N`