Question

a moving train brought to rest within 20 seconds by applying brakes . Find the initial velocity, if the retardation due to brakes is 2metre /second

Answer 1

Answer:

40m/s

Explanation:

v=0. t=20s. a= -2m/s^2. u=?

From equations of motion

v = u + at

0 = u + -2 × 20

0 = u - 40

- u = -40

minus symbols on both sides cancel

u = 40m/s