A ball of mass `4 kg` moving with a velocity of `12 m//s` impinges directly on another ball of mass `8 kg` moving with velocity of `4 m//s` in the same direction. Find their velocities after impact and calculate the loss of `KE` due to impact if `e =0.5`.

Explanation

To solve the problem step by step, we will follow the principles of conservation of momentum and the coefficient of restitution.

### Step 1: Understand the Problem
We have two balls:
- Ball 1: mass \( m_1 = 4 \, \text{kg} \), initial velocity \( u_1 = 12 \, \text{m/s} \)
- Ball 2: mass \( m_2 = 8 \, \text{kg} \), initial velocity \( u_2 = 4 \, \text{m/s} \)
- Coefficient of restitution \( e = 0.5 \)

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