The friction coefficient bettween an athelete's shoes and the ground is 0.90. Suppose a superman wears these shoes and races for 50 m. There is no upper limit in his capacity of running at high speeds. A. Find the minimum time that he will have to take in completing the 50 m starting from rest. b. Suppose he takes exactly this minimum time to complete the 50 m, what minimum time will he take to stop?

Explanation

To solve the problem, we will break it down into two parts as specified in the question.

### Part A: Finding the Minimum Time to Complete 50 m

1. **Identify the Given Data:**
- Coefficient of friction (μ) = 0.90
- Distance (s) = 50 m
- Initial velocity (u) = 0 m/s (starting from rest)
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