7. Assertion : Strain is a unitless quantity. Reason : Strain is equivalent to force.

(a)        If both assertion and reason are true and the reason is the correct explanation of the assertion.

(b)        If both assertion and reason are true but reason is not the correct explanation of the assertion.

(c)        If assertion is true but reason is false.

(d)        If the assertion and reason both are false.

(e)        If assertion is false but reason is true.

Explanation-

(c) Strain is the ratio of change in dimensions of the body to the original dimensions. Because this is a ratio, therefore it is dimensionless quantity.

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