Question

a train of waves is moving at a speed of 40km/h at 10:00am and at 50km/h at 10:15am . Assuming that the train moves along a straight track and the acceleration is constant . find out the value of the acceleration

Answer 1

Time from 10:00 To 10:15 is 15 minutes.
therefore, T=15 minutes==1/4hr
v(final velocity)=50 km/hr
u(initial velocity)=40 km/hr
Since, a= v-u/t
a=50- 40/1/4= 10/1/4=10*4=40 km/hr^2
Therefore, a=40 km/hr^2

Answer 2

acceleration = ( final velocity - initial velocity ) / time duration for the change 
                     = (50 kmph - 40 kmph ) / [1/4 hour ] = 40 km/hour²
                 = 40 * 1000 / 3600²  m/sec² = 0.00308 m/sec²