Physics education research, electronic materials, and the musings of Christopher Moore, Ph.D.

1.Statement: A mouse starts climbing up a ladder with uniform speed u wrt ladder and at the same time ladder is released to fall from rest. After what time the mouse is again at its initial position wrt the ground if
a) mass of mouse is negligible wrt ladder
b) mass of mouse be m and that of ladder be M

PS:initially the mouse is at the bottom of the ladder and ladder is held vertical and then released at t=0

i was able to think for the first part...
as the mouse have acceleration=g (downward)
n initial velocity =u (which is uniform actually) so in order to have displacement=0
we can write.. so we have t=2u/g
but what about 2nd part??