Question

6. A train moving with a velocity of 20 ms is brought
to rest by applying brakes in 5 s. Calculate the
retardation
Ans. 4 m s2
​

Answer 1

$v = 20 \: ms \\ u = 0 \\ t = 5sec \: \\by \: using \: this \: formula \: given \: below \: u \: get \: it \: \\ v = u + at \\ 20 = 0 +a \times 5 \\ 5a = 20 \\ a = \frac{20}{5} \\ so \: acceleration \: = 4ms$

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