A truck travelling at 50 kph. It brakes retarding it at 5 m/sec. How long it will take up to stop the truck? What distance reached it when it finally stop?

Answer 1

assume you mean 5 m/s^2

50 *1000/3600 = 13.9 m/s

v = 13.9 - 5 t
0 = 13.9 - 5 t

t = 13.9/5

average speed during stop = 13.9/2

d = (13.9/2) (13.9/5)

or
d = Vi t - .5 (5) t^2
d =13.9(13.9/5)-.5 (5) (13.9^2)/5^2
= .5 *13.9^2/5 the same