Question

A man drawing a bucket of water falls back when the rope snaps. This is because of
A. Law of gravitation
B. 1st law of motion.
C. Newton’s second law of motion.
D. Newton’s third law of motion.

Answer 1

Hint:- Newton’s third law of motion states that if there is an action on body A due to body B ,then there is an equal amount of reaction on body B due to body A . In case of tension of the rope if the rope gets snapped then there will be formed an action-reaction pair between the man and the bucket hence there is a reaction force on the man due to which the man falls back.

Complete step-by-step solution:-
A diagram is shown here according to the situation , man is drawing the bucket against a force that is gravitational pull / gravity . As the diagram shows there is equal amount of force in the rope at both of the ends that is at man end and the bucket end.

The acceleration of the bucket is upwards or we can say if acceleration is zero then also there is a constant velocity of bucket in upwards direction , it means man is applying a force F on the rope in backward direction or we can say man is pulling the rope , as the rope gets snapped suddenly , the man is still in transition phase of action- reaction pair and falls backward due to the force which he applied on the rope.
It means there is an action- reaction pair between man and the rope .
Hence this is due to Newton’s third law of motion.
Option (D) is the correct answer.

Note:- When you jump , your legs apply a force to the ground , and the ground applies and equal and opposite reaction force that lifts you up in the air.
The same principle is also used in engineering and designing of rockets and other projectile devices. During the launch , the burning fuel exerts a downward force, and the reaction force pushes the rocket up into the air.
In reaching space, the rocket applies its rear thrusters to move forward, which provides another example of how we can take advantage of reaction forces.