Non-conservative Forces and Energy – Rankers Physics

Potential Energy & Equilibrium: Practice Problem & Solution

Assertion (A): When a non-conservative force is involved in a system, it may dissipate energy. Reason (R): The work done by a non-conservative force is always negative.
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 Potential Energy & Equilibrium. Understanding the underlying formula is key to arriving at the correct answer below:

Assertion is true: Non-conservative forces like friction or air resistance dissipate mechanical energy into other forms (e.g., heat).

Reason is false: The work done by a non-conservative force is not always negative. For example, an applied external force can be non-conservative and do positive work on a system.

Thus, A is true but R is false.

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