Question

Swimming is possible on account of (A) First law of motion (B) second law of motion (C) Third law of motion (D) Newton's law of gravitation

Short answer

Swimming is possible primarily due to the (C) Third law of motion. When a swimmer pushes water backwards with their hands and feet, the water exerts an equal and opposite force, propelling the swimmer forward.

Step-by-step solution

Brief Overview of Newton's Laws of Motion and Law of Gravitation

Before defining which law is responsible for swimming, let us briefly overview each of them: (A) First law of motion (Inertia) states that an object at rest will stay at rest and an object in motion will stay in motion unless acted upon by an external force. (B) Second law of motion (F = ma) states that the acceleration of an object is directly proportional to the net force acting upon it and inversely proportional to its mass. (C) Third law of motion (Action and Reaction) states that for every action, there is an equal and opposite reaction. (D) Newton's law of gravitation states that every particle in the universe attracts every other particle with a force proportional to the product of their masses and inversely proportional to the distance between their centers squared.

Relation between Swimming and Newton's Laws

Now let's see how these laws apply to swimming. (A) Inertia is an essential phenomenon; however, it does not directly explain swimming as it only states how objects respond to external forces. (B) While swimming, the force exerted by the swimmer on water propels them forward. However, the second law of motion does not specify the action-reaction principle that makes swimming possible. (C) Third law of motion involves action and reaction forces and plays a significant role in swimming. When a swimmer pushes water backwards with their hands and feet, the water exerts an equal and opposite force, propelling the swimmer forward. (D) The law of gravitation has minimal direct relevance to swimming as it governs how celestial bodies attract one another.

Identifying the Correct Answer

Based on the analysis above, we can conclude that: Swimming is possible on account of (A) First law of motion - Not the correct answer (B) Second law of motion - Not the correct answer (C) Third law of motion - The correct answer (D) Newton's law of gravitation - Not the correct answer Therefore, the correct answer is (C) Third law of motion.