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Question
We have two identical metal sheets. One of them is rubbed with sand paper and the other with ordinary paper. The one rubbed with sand paper shines more than the other. Give reason.
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Solution
While rubbing with sandpaper, more frictional force is produced between the layers of metal sheet and sandpaper which causes more force on dust particles and they are removed easily, so it will shine more.
But in case of ordinary paper, the force of friction is not sufficient to remove all the dust, so it will shine less in this case.
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