A car moving along a straight highway with speed of 126 km `h^(-1)` is brought to a stop within a distance of 200 m. What is the retardation of the car (assumed uniform) and how long does it take for the car to stop ?

Explanation

To solve the problem, we will follow these steps:

### Step 1: Convert the speed from km/h to m/s
The initial speed \( u \) of the car is given as 126 km/h. To convert this to meters per second, we use the conversion factor \( \frac{5}{18} \).

\[ u = 126 \, \text{km/h} \times \frac{5}{18} = 35 \, \text{m/s} \]
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