Question

A LCR circuit is at resonance for a capacitor C, inductance L and resistance R. Now the value of resistance is halved keeping all other parameters same. The current amplitude at resonance will be now: 

(1) Zero 

(2) double 

(3) same 

(4) halved

Answer 1

Correct option is : (2) double  

In resonance \(\mathrm{Z}=\mathrm{R}\)

\(\mathrm{I}=\frac{\mathrm{V}}{\mathrm{R}}\)

\(\mathrm{R} \rightarrow\)halved

\(\Rightarrow \mathrm{I} \rightarrow 2 \mathrm{I}\)

I becomes doubled.