Q21 of 59 Page 254

The velocity of car is 18 ms-1. Express this velocity in kmh-1.

Velocity of Car = 18 ms-1

To express this velocity in kmhr-1 we need the conversion factor which is calculated as under:


1 km = 1000 m


So, 1 m = km


Now, 1 hr = 60 minutes = 60 × 60 s = 3600 s


So, 1 s = hr


Now, Velocity of car = 18


= 18


= kmh-1


= 64.8 kmh-1


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