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  4. In the figure-3.90 shown, the net work done by the tension when the bigger block of mass M touches the ground is :

Q. In the figure-$3.90$ shown, the net work done by the tension when the bigger block of mass $M$ touches the ground is :Physics Question Image

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Solution:

Work done by tension $=$ zero as string is massless and frictionless which can never do work.

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