A car moving at 20 m/s brakes with constant deceleration and stops after 5 s. How far does it travel while braking?
Answer and explanation
Correct answer: B. 50 m
- Step 1: Deceleration is uniform, so the average speed is (20 + 0) / 2 = 10 m/s. Step 2. Distance = 10 x 5 = 50 m. Answer: 50 m. Why not the others: Using the initial speed for the whole time overestimates the distance.
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