A car decelerates uniformly from 30 m/s to 0 in 6 seconds. Its acceleration is:
A−5 m/s²
B+5 m/s²
C−30 m/s²
D+30 m/s²
Answer & Solution
Correct answer: A. −5 m/s²
a = (v − u) / t = (0 − 30) / 6 = −5 m/s². Negative sign indicates deceleration (slowing down). The car loses 5 m/s of speed every second.
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