Problem

Two trains are moving with velocities

v_1 = 10 \text{ ms}^{-1}

and

v_2 = 20 \text{ ms}^{-1}

on the same track in opposite directions. After the application of brakes if their retarding rates are

a_1 = 2 \text{ ms}^{-2}

and

a_2 = 1 \text{ ms}^{-2}

respectively, then the minimum distance of separation between the trains to avoid collision is a. 150 m b. 225 m c. 450 m d. 300 m