Question

A train moving west with an initial velocity of 20 m/s accelerates at 4 m/s2 for 10 seconds. During this time, the train moves a distance of
meters.

Answer 1

Use s = ut + 1/2 a t^2.

s = 20(10) + 0.5(4)(10^2) = 200 + 2(100) = 200 + 200 = 400 m.

(The train moves 400 m west.)