A boy standing on a stationary lift (open from above) throws 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 long does the ball take to return to his hands?

Explanation

To solve the problem step by step, we will analyze both scenarios presented in the question.

### Step 1: Analyze the first case (stationary lift)
- **Given:**
- Initial speed of the ball, \( u = 49 \, \text{m/s} \)
- Acceleration due to gravity, \( a = -9.8 \, \text{m/s}^2 \) (negative because it acts downward)
- Displacement, \( s = 0 \) (the ball returns to the same height)

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