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An object, moving with a speed of 6.25 m/s, is decelerated at a rate given by : dv/dt = -2.5√v where v is the instantaneous speed. The time taken by the object, to come to rest, would be:

1. 2 s
2. 4 s
3. 8 s
4. 1 s

Correct answer: 2 s

Solution

The deceleration equation indicates that the rate of change of speed is proportional to the square root of the speed. By integrating this relationship, we find that the time taken for the object to decelerate from 6.25 m/s to 0 m/s is 2 seconds.

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