Question

If a train starts from rest and after 0.5 hours travels at a speed of 75 km/hr, what is its

acceleration?

Answer 1

150 km/hr²

Step-by-step explanation:

The data for the motion of the train includes;

The train starts from rest, therefore, the initial velocity of the train, u = 0 km/hr

The speed of the train after 0.5 hours, v = 75 km/hr

The change in time during the motion of the train, Δt = 0.5 hours

The acceleration, 'a', is the rate of change of velocity with time;

`a = (\Delta v)/(\Delta t) = (v - u)/(\Delta t)`

Therefore, we have;

a = (75 km/hr - 0 km/hr)/(0.5 hr) = 150 km/hr²

a = 150 km/hr² = 150 km/hr² × 1,000 m/km × hr²/(3,600 s)² = 5/432 m/s²

The acceleration of the train, a = 150 km/hr² = 5/432 m/s².