A block of weight 20 N is placed on a horizontal table and a tension T is applied on the block . Tension can be increased to 8 N before the block begins to slide . A force of 4 N keeps the block moving at constant speed , once it has been set in motion . Find the coefficients of static friction and kinetic friction].

Explanation

To solve the problem, we need to find the coefficients of static and kinetic friction for a block placed on a horizontal table. The block has a weight of 20 N, and we are given two key pieces of information: the maximum tension before the block begins to slide (8 N) and the force required to keep the block moving at a constant speed (4 N).

### Step-by-Step Solution:

1. **Identify the Forces Acting on the Block:**
- The weight of the block (W) is given as 20 N. This weight acts downwards.
- The normal force (N) acts upwards, which balances the weight of the block on the horizontal table.
- The tension (T) is applied horizontally, and we need to consider the frictional forces acting against this tension.
...