Question

If a balloon filled with air abd its mouth is united is reliaed in the downward direction its move up why?

Answer 1

this is due to the Newton's third law which says that if an object exerts force on other object.then the other object also exerts force on first object which is equal in magnitude and opposite in direction.the balloon moves in the opposite direction to that escaping air.the momentum of balloon with,when the air escapes with same velocity,the balloon moves in opposite direction to balance the momentum of the escaping air.