Man on Ground Forces – Rankers Physics

Third Law of Motion: Practice Problem & Solution

Assertion (A): A man standing at rest on ground. Force exerted by man on ground is equal to weight of man. Reason (R): Earth attracts man by force \(mg\) hence by Newton's third law, man also attracts earth by same force.  
Both (A) & (R) are true and the (R) is the correct explanation of the (A)
Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(A) is true but (R) is false
Both (A) and (R) are false

Short Solution (Best for NEET):

To solve this problem, we apply the core principles of Third Law of Motion. Understanding the underlying formula is key to arriving at the correct answer below:

Assertion (A) is true: the man exerts a force equal to his weight on the ground. Reason (R) is true by Newton's third law of gravitation for action-reaction. However, Reason (R) explains gravitational forces, not the contact force on the ground, so it is not a correct explanation for (A).

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