An inclined plane is moving up with constant velocity `v`. A block kept on incline is at rest. Calculate the work done by gravity, friction force, and normal reaciton on block in time interval of t.

Options

A. The contact force between block and inclined is parallel to the incline
B. The contact force between block and inclined is of the magnitude `m(g + a)`
C. The contact force between block and inclined is perpendicular to the incline
D. The contact force is of the magnitude `mg cos theta`

Answer

b

Explanation

Fig. `F_(c) = sqrt(f^(2)+ N^(2)) = m(g + a)`

`f = m(g sin +a)sin theta , N = m(g + a) cos theta`
Net contact force `F_(c) = sqrt(f^(2) + N^(2) = m(g + a)`