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
20