A boy standing on a stationary lift ( open from above ) thrown a ball upwards with the maximum initial speed he can, equal to ` 49 ms^(-1)`. How much time does the ball take to return to his hands ? If the lift starts moving up with a uniform speed of ` 5 ms^(-1)` and the boy again throws the ball up with the maximum speed he can , how hoes the ball take to return to his hands ?

Explanation

To solve the problem, we will analyze both cases step by step.

### Case 1: Lift is Stationary

1. **Given Data**:
- Initial velocity of the ball, \( u = 49 \, \text{m/s} \) (upward)
- Acceleration due to gravity, \( g = 9.8 \, \text{m/s}^2 \) (downward)
- Displacement when the ball returns to the boy's hand, \( s = 0 \)
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