Question

Why does a swimmer push water backward with his hands in order to swim forward?

Answer 1

Hint: In order to solve this question, we should first know about push or applying Force. Force is the external agent when applied to a body, it has the tendency to change the state of motion of a body either it can change the velocity of a body or change the direction of a moving body. Here we will discuss the force applied by the swimmer and the cause behind it that makes the swimmer move forward.

Complete answer:
As we see that, a swimmer always applies some force with his hands to push water backward continuously and the swimmer moves forward. The main reason behind it is Newton’s Third law of motion which states that every action has an equal and opposite reaction which means if you apply some force in a particular direction to a body, it will exert an equal amount of force on you but in the opposite direction.

So, when swimmers push water backwards with some force, water also exerts the same amount of force on the swimmer but in the opposite direction which is forward and hence with the help of this force the swimmer moves forward.

Hence, a swimmer pushes water backward and moves forward due to Newton’s Third law of motion.

Note: It should be remembered that, the magnitude of force on anybody is simple the product of mass of a body and the acceleration produced in it due to applied force, mathematically force is calculated as $F = ma$ and SI unit of force is called Newton denoted by $N$.