question_answer

A stone dropped from the window of a stationary bus takes 5 seconds to reach the ground. In what time the stone will reach the ground when the bus is moving with (a) constant velocity of \[80\text{km}{{\text{h}}^{-1}}\] (b) constant acceleration of\[2\text{km}{{\text{h}}^{-2}}\] ?

Answer:

                (a) 5 seconds (b) 5 seconds. In both cases, initial vertical velocity is zero, downward acceleration is equal to \['g'\] and also vertical distance covered is same.