what is normal reaction force?
Normal reaction force or normal force is the the force which acts perpendicular to the plane, on which an object is lying.
e.g. weight of an object resting on a table is balanced by normal force(N) exerted by the table.
N = mg.
Some examples of reaction force:-
Horse pulling a cart
The horse can pull and move a cart by exerting a force on the ground. In turn, the horse experiences a reaction force of equal magnitude in the opposite direction that causes the cart to move in that direction.
In this case, the action force is the force applied by the horse on the ground and reaction force is the force experienced by the horse from the ground.
Rockets
Rockets work on the principle of Newton’s IIIrd law of motion. In rockets, large amounts of hot gases are allowed to exit through a narrow opening. The fast moving gases exert a force on the rocket that in turn pushes the rocket upward.
In this case,
Action force → Exerted by the rocket on the exhaust gases
Reaction force → Exerted by the gases on the rocket