Question

A train moving with a velocity of 20 m s-1 is brought to rest by applying brakes in 5 s. Calculate the retardation.

February 27, 2024

Answer

According to equation of motion

v = u + at

Given,

u = 20 m s^-1,

v = 0,

t = 5 s

Substituting the values in the formula above, we get,

0 = 20 + a × 5

or, 0 = 20 + 5a

or, 5a = – 20

or, a = -20/5 = -4 m s^-2

Hence, Retardation is 4 m s^-2

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