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Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R. Assertion A : Product of Pressure (P) and time (t) has the same dimension as that of coefficient of viscosity. Reason R : Coefficient of viscosity = Force / Velocity gradient Choose the correct answer from the options given below. (1) Both A and R true, and R is correct explanation of A. (2) Both A and R are true but R is NOT the correct explanation of A. (3) A is true but R is false. (4) A is false but R is true.

1. Both A and R true, and R is correct explanation of A.
2. Both A and R are true but R is NOT the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Correct answer: A is true but R is false.

Solution

The assertion is correct because the product of pressure and time does indeed have the same dimensions as the coefficient of viscosity, which is derived from the relationship between force and velocity gradient. However, the reason provided is incorrect because the definition of the coefficient of viscosity does not directly relate to the dimensional analysis of pressure and time.

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