Assertion :On polishing the surface the friction decreases up to a certain limit but increases beyond that. Reason: On polishing the surface, the irregularities are cut off but beyond a certain limit, the surface molecules exert strong attractive forces on each other.

Both Assertion and Reason are correct and Reason is the correct explanation for Assertion

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Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion

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Assertion is correct but Reason is incorrect

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Both Assertion and Reason are incorrect

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Solution

The correct option is A Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
When the surface is polished beyond a certain limit, the molecules exert strong attractive forces on each other. This is called surface adhesion. To overcome these forces, additional forces are required. Thus the frictional forces increase.

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Choose the correct option.

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(a) Both assertion and reason are correct and the reason is correct explanation of assertion
(b) Both assertion and reason are correct, but reason does not explain assertion.
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(d) Both assertion and reason are incorrect
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