A car travelling at 72 km/h takes a U – turn in 10 seconds. What is the acceleration of the car ?A 4 m/s2 B 8 m/s2 C 12 m/s2 D 6 m/s2

To solve this problem, we first need to convert the speed from km/h to m/s because the standard unit of acceleration is m/s².

1. Convert speed from km/h to m/s: 72 km/h = 72 * 1000 m/3600 s = 20 m/s

2. The car takes a U-turn, which means it changes its velocity direction by 180 degrees. But the magnitude of the velocity remains the same. So, the change in velocity (final velocity - initial velocity) is 2 * initial velocity.

3. Change in velocity = 2 * 20 m/s = 40 m/s

4. Acceleration is the rate of change of velocity. It is given by the formula: Acceleration = Change in velocity / Time taken

5. Substituting the given values in the formula: Acceleration = 40 m/s / 10 s = 4 m/s²

So, the acceleration of the car is 4 m/s². The answer is A: 4 m/s².