Mutual Attraction and Kinetic Energy – Rankers Physics

Momentum Conservation: Practice Problem & Solution

Assertion (A): Two objects are moving towards each other due to mutual attraction. The kinetic energy of the system remains constant. Reason (R): Total linear momentum of the system consisting both the objects remain constant even in the presence of external forces.  
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 Momentum Conservation. Understanding the underlying formula is key to arriving at the correct answer below:

Assertion (A) is false; as objects move towards each other due to mutual attraction, their potential energy decreases, and kinetic energy increases, so it does not remain constant.

Reason (R) is false; total linear momentum of a system is conserved only in the absence of external forces, not 'even in the presence of external forces'. Therefore, both (A) and (R) are false.

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