JEE Main202228 Jun 2022Morning ShiftPhysicsUnits and DimensionsActual
Assertion A: Product of Pressure P and time t has the same dimension as that of coefficient of viscosity. Reason: Coefficient of viscosity = Force Velocity gradient
Options
- ABoth A and R true, and R is correct explanation of A.
- BBoth A and R are true but R is NOT the correct explanation of A.
- CA is true but R is false.
- DA is false but R is true.
Correct answer
C. A is true but R is false.
Step-by-step solution
Viscous force is given by F = η A d v d t , here, A is area and d v d t is velocity gradient. Thus, η = F A d v d t . Now, P t = F A t = η d v d t t Then, P t = M L - 1 T - 1 = η Thus, assertion is true but reason is false.