Question

why+do+we+need+to+run+a+certain+distance+before+getting+into+a+moving+bus

Answer 1

momentum of the moving bus assume it as some #.and in your still position your momentum is 0 so the bus moves more than your speed so you can't get into the moving bus

Answer 2

Because a moving bus may stop across a certain distance when the bus driver uses brake.. so that before getting into moving bus we need to run