Topic: Newton's Third Law of Motion.
Why does a swimmer push the water backward?
No.
There is a hole in the boat.
Now, how will you reach the shore?
Don't worry.
Do as I say.
Jump in the water and push the water backward with your hands.
This will help you to move forward towards the shore.
No.
You are not pushing the water backward.
See.
You are moving forward towards the shore.
Do you know why you were able to move forward by pushing the water backward?
To understand this, you need to learn about Newton's third law of motion.
Newton's third law of motion states that, for every action, there is an equal and opposite reaction.
No.
Not that action.
Wait, let me explain.
When we swim, we apply force and push the water backward with the help of our hands.
This is action.
In response to this action, the water pushes us forward with an equal force.
This is reaction.
Thus, in order to move forward and swim, the swimmer pushes the water backward.