Question

A motorbike moves in a straight road. The velocity at point a is 36 km/hr, it presses the accelerator paddle and reaches point b in 10 sec. The velocity at point b is 54km/hr



find the average acceleration of the car from point a to point b?

Answer 1

Average velocity is 50 km/h

Answer 2

By work-energy theorem increase in KE due to the work done on the body of mass m to accelerate it to a velocity v is given by

W = ½mv2 - ½mu2

Here, u = 0

=> W = ½mv2

Velocity v is acquired in time t’, so

v = at’

=> W = ½m(at’)2