Q 11-01-157JEE MainJEE Main 2022 (25 Jul, Shift 1)Medium
If momentum $P$, area $A$ and time $T$ are taken as fundamental quantities, then the dimensional formula for coefficient of viscosity is
Answer: (A) $[PA^{-1}T^0]$
$[\eta] = [\text{M}\text{L}^{-1}\text{T}^{-1}]$. Write $\eta = P^aA^bT^c$ with $[P] = [\text{M}\text{L}\text{T}^{-1}]$ and $[A] = [\text{L}^2]$:
M: $a = 1$. L: $a + 2b = -1\Rightarrow b = -1$. T: $-a + c = -1\Rightarrow c = 0$.
So $[\eta] = [PA^{-1}T^0]$.
Solution by Sreeraj P, M.Sc Physics