A rubber ball of mass `0.4` kg hits the ground at same angle without any change in speed . If the speed of ball is 1 m/s and the period of contact between the ball and floor is `0.4` s, find the average force exerted by the ball on the ground .

Explanation

To solve the problem, we need to find the average force exerted by the ball on the ground when it hits the ground and bounces back. Here are the steps to arrive at the solution:

### Step 1: Identify the given data
- Mass of the ball, \( m = 0.4 \, \text{kg} \)
- Speed of the ball before hitting the ground, \( u = 1 \, \text{m/s} \) (downward)
- Speed of the ball after bouncing, \( v = 1 \, \text{m/s} \) (upward)
- Time of contact with the ground, \( t = 0.4 \, \text{s} \)

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