If L, R, C denote inductance, resistance and capacitance, respectively. Then dimensions of  $\frac{\mathrm{L}}{{\mathrm{R}}^2\mathrm{C}}$are

$\frac{\mathrm{L}}{\mathrm{R}}=$time constant of L-R circuit = $\left[{\mathrm{M}}^0{\mathrm{L}}^0\mathrm{T}\right]$

RC = time constant of R-C circuit = $\left[{\mathrm{M}}^0{\mathrm{L}}^0\mathrm{T}\right]$

$\frac{{\mathrm{L}}^{ }}{{\mathrm{R}}^2\mathrm{C}}=\left(\frac{\mathrm{L}}{\mathrm{R}}\right)\times \frac{1}{\mathrm{RC}}=\frac{\left[{\mathrm{M}}^0{\mathrm{L}}^0\mathrm{T}\right]}{\left[{\mathrm{M}}^0{\mathrm{L}}^0\mathrm{T}\right]}=\left[{\mathrm{M}}^0{\mathrm{L}}^0{\mathrm{T}}^0\right]$