$\frac{1}{\text{RC}}$
$\frac{\text{R}}{\text{L}}$
$\frac{1}{\sqrt{\text{LC}}}$
Explanation:
þ Time constant t = RC in RC circuit
frequency $=\frac{1}{\tau}=\frac{1}{\text{RC}} \ ...(\text{i})$
þ Time constant in LR circuit is $\tau=\frac{\text{L}}{\text{RC}}$
frequency $\frac{1}{\tau}=\frac{\text{R}}{\text{L}} \ ...(\text{ii})$
þ eq. (i) & (ii) multiply
frequency $=\frac{1}{\text{LC}}$
frequency $=\frac{1}{\sqrt{2\text{C}}}$
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