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प्रश्न
The change in velocity of a motorbike is 54 kmh−1 in one minute. Calculate its acceleration in (a) ms−2 (b) kmh−2.
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उत्तर
Change in velocity = 54 kmh−1 = `54xx1000/3600` ms−1 = 15 ms−1
Time = 1 minute = 60 s
Acceleration (a) = `"Change in velocity"/"Time"`
= `15/60` ms−2
a = 0.25 ms−2
a = `0.25xx1000/3600xx3600` kmh−2 = 3240 kmh−2
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