A driver can stop his car from the red signal at a distance of 20 m when he is driving at 36 kmph and 41.25 m when he is driving at 54 kmph. Find his reaction time.

Explanation

To solve the problem, we need to determine the driver's reaction time based on the distances he can stop his car at two different speeds. We'll use the equations of motion to find the relationship between the distances, speeds, and reaction time.

### Step-by-Step Solution:

1. **Convert Speeds to Meters per Second:**
- The first speed is 36 km/h. To convert this to meters per second:
\[
u_1 = 36 \times \frac{5}{18} = 10 \text{ m/s}
...