A tanker full of a liquid, is static on a straight road with no friction. Outlet pipe of the tanker is on down and corner of it and Its closed by a stopper.
Describe movement (motion) of tanker after we suddenly open the outlet pipe!
and sorry if my english is weak!
Since outlet pipe is located under the tanker, so the velocity of the liquid will be directed downward and momentum in the horizontal direction is not changed. If momentum in the horizontal direction is not changed, the horizontal speed of the tanker is equal to zero.