Q30 of 124 Page 74

For how long should a force of 100 N act on a body of 20 kg so that it acquired a velocity of 100 m/s?

Force F = m (v-u)/t ........equation 1

u is initial velocity = 0


v is final velocity = 100m/s


F = 100N


m = 20kg


Putting these values in equation 1 we can find time t


100 = 20(100-0)/t


t = 20 seconds


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