A block of mass `m` is at rest on a rought wedge as shown in figure. What is the force exerted by the wedge on the block?

Explanation

Since, the block is permanently at rest, it is in equilibrium. Net force on it should be zero. In this case, only two forces are acting on the block
(i)Weight `=mg` (downwards).
Contact force (resultant of normal reation and friction forces) applied by the wedge on the block.
For the block to be in equilibrium, these two forces should be equal and opposite. Therefore, force exerted by the wedge on the block is `mg` (upwards).