A man getting down a running bus falls forward because
Due to inertia of rest, road is left behind and man reaches forward
Due to inertia of motion upper part of body continues to be in motion in forward direction while feet come to rest as soon as they touch the road
He leans forward as a matter of habit
Of the combined effect of all the three factors stated in (a), (b)and (c)
A man getting down a running bus falls forward because
This happens because till he is in the bus he has same inertia of motion w.r.t the bus but as he touches the ground his body still has inertia of motion wr.t the ground but his feet are stationary on the road.
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