b
(b)
Let $R_H=k h^a e^b \quad \dots(i)$
As, $R=\frac{V}{I}$
$\therefore {\left[R_H\right] } =\left[ ML ^2 T ^{-3} A ^{-2}\right]$
$\Rightarrow h =E \cdot t$
$\Rightarrow {[h] }=\left[ ML ^2 T ^{-1}\right]$
$e=I \cdot t \Rightarrow[e]=[ A \cdot T ]$
Substituting above values in Eq. $(i)$, we have
${\left[ ML ^2 T ^{-3} A ^{-2}\right] }=k\left[ ML ^2 T ^{-1}\right]^e[ AT ]^b$
$=k\left[ M ^a L ^{2 a} T ^{-a+b} A ^b\right]$
Equating dimensions, we get
$a=1 \text { and } b=-2$
Hence, $\quad R_H=k\left(\frac{h}{e^2}\right)$
So, dimensions of hall resistance are same as that of $\frac{h}{e^2}$.