Question

Why a men pulling a bucket of water from a well, suddenly fell down on breaking down of a rope.?

Answer 1

the force exerted by the bucket  of water in a well is the reaction to the action provided by a man who is pulling it.when the rope breaks ,that reaction force does not exist anymore and by law of inertia ,he tends to keep pulling away from the well and falls in the backward direction when the force disappears.

every action has a reaction.Force is a paired process.No single force exists

this situation is similar to that of the game of Tug of war.The opponent team provides the reaction to the action of your team.

hope this helps.....