Work in Inertial Frames – Rankers Physics

Work Done by Constant and Variable Forces: Practice Problem & Solution

Assertion (A): Work done by a force is always same in all inertial frame of references. Reason (R): Work is an invariant physical quantity.  
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 Work Done by Constant and Variable Forces. Understanding the underlying formula is key to arriving at the correct answer below:

Work done (\(W = \vec{F} \cdot \vec{d}\)) depends on displacement (\(\vec{d}\)) which is frame-dependent in different inertial frames. Therefore, work is not always the same and is not an invariant quantity. Both Assertion and Reason are false.

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