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## QuestionPhysicsClass 12

A $$15$$ micro Farad capacitor is connected to a $$220\text{V}, 50\text{Hz}$$source Find the capacitive reactance and current $$($$rms and peak$$)$$ in circuit. If the frequency is doubled what happens to the capacitive reactance and current.

The capacitive reactance $$=\frac 1{2\mathit{\pi fC}}$$
Here $$f=50\mathit{Hz}$$ and $$C=15$$ micro farad
So capacitive reactance $$=212$$ ohm
Rms current= $$\frac V{\mathit{reactance}}=\frac{220}{212}=1.03A$$
Peak current $$=\sqrt2I=1.414\times 1.03=1.47A$$
When the frequency is doubled the capacitive reactance will be halved than the current will also be doubled.