Q19 of 54 Page 290

It is required to increase the velocity of a scooter of mass 80 kg from 5 to 25 m s-1 in 2 second. Calculate the force required.

Mass = 80 kg
Initial velocity, u = 5 m s-1
 final velocity, v = 25 m s-1
 Time, t = 2 sec

Rate of change of momentum = force applied


Force = = = = 800N


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