Dimensions of resistance in an electrical circuit, in terms of dimension of mass M, of length L, of time T…

Dimensions of resistance in an electrical circuit, in terms of dimension of mass M, of length L, of time T and of current I, would be
A $ML^2T^{-2}$
B $ML^2T^{-1}I^{-1}$
C $ML^2T^{-3}I^{-2}$
D $ML^2T^{-3}I^{-1}$

Detailed Solution

Resistance: $R = \dfrac{V}{I}$
Potential difference $V = \dfrac{\text{work}}{\text{charge}} = \dfrac{[ML^2T^{-2}]}{[IT]} = [ML^2T^{-3}I^{-1}]$
$[R] = \dfrac{[V]}{[I]} = \dfrac{[ML^2T^{-3}I^{-1}]}{[I]}$
$[R] = [ML^2T^{-3}I^{-2}]$
Check using power: $P = I^2R \Rightarrow [R] = \dfrac{[ML^2T^{-3}]}{[I^2]} = [ML^2T^{-3}I^{-2}]$

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