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

Solution Explained:

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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