Question

a moving train is brought to rest in 20 second by applying brake find its initial velocity if acceleration due to break is -2m per second Square

Answer 1

${v}^{2} = vot + \frac{1}{2} a {t}^{2} \\ 0 = vo(20) - 20 \\ vo = \frac{20}{20} \\ vo = 1 m {s}^{ - 1}$
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