A car is traveling at 40km/hr and the driver puts on the brakes bringing the car to rest in a time of 6s. What is the magnitude of the average acceleration of the car?
Correct answer: C. 24,000 km/hr²
- A. 240 km/hr²
- B. 12,000 km/hr²
- C. 24,000 km/hr²
- D. 30,000 km/hr²
Explanation
The correct answer is Option C: 24,000 km/hr². To find the average acceleration, use the formula a = (v_f - v_i) / t, where v_f is the final velocity (0 km/hr), v_i is the initial velocity (40 km/hr), and t is the time (6 seconds). Converting the units to km/hr² by multiplying by 3600 to account for time in seconds results in an acceleration of 24,000 km/hr². Options A, B, and D result from miscalculations or incorrect unit conversions.
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