Question

A bus of mass 10000 kg is moving with speed 72 kmh-¹ calculate the work done to Stop the Bus.​

Answer 1

        $\text{Mass of bus}(m) = 10000\: kg$

        $\text{Initial speed of bus}(u) = 72 \: km/h = 20 \: m/s$

        $\text{Final speed of bus}(v) = 0$

$\implies \: K.E_i = \dfrac12mv^2 = 2000000 \: J$

$\implies \: K.E_f = 0$

        $\text{Work done} = \text{Change in }K.E$

$\implies \: W = \triangle{K.E} = K.E_f - K.E_i$

$\implies \: \boxed{W = 2000000 \: J}$

Answer 2

Answer:

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