Question

a train is moving at 45km/h when a coupling breaks and the last car separates from the train. as soon as the car separates, the brakes are automatically applied, locking all wheels of the runaway car and causing a uniform decelaration of 5 m/s^2. determine the distance the car travels before coming to a stop?

Answer 1

Vo = 45km/h = 45000m / 3600s=12.5 m/s = Initial velocity.

d = (Vf^2-Vo^2)/2a,
d = (0-(12.5)^2) / -10 = 15.63 m.