A body of mass `m` is kept on a rough horizontal surface of friction coefficient `mu` . A force `P` is applied horizontally , but the body is not moving .Find the net force `F` exerted by the surface on the body .

Explanation

To solve the problem step by step, we need to analyze the forces acting on the body that is at rest on a rough horizontal surface.

### Step 1: Identify the forces acting on the body
- The weight of the body (W) acting downwards: \( W = mg \)
- The normal force (N) acting upwards from the surface.
- The applied force (P) acting horizontally to the right.
- The frictional force (f) acting horizontally to the left, opposing the applied force.

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