Non-Conservative Forces and Work – Rankers Physics

Potential Energy & Equilibrium: Practice Problem & Solution

Assertion (A): The work done by a non-conservative force is always negative. Reason (R): When a non-conservative force is involved in a system, it always dissipates energy.
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:

Work done by non-conservative forces can be positive (e.g., applied force) or negative (e.g., friction), so (A) is false.

Non-conservative forces can dissipate (friction) or add (engine thrust) energy. So (R) is also false.

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