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A series LCR circuit is connected to an alternating source of emf E. The current amplitude at resonant frequency is I0. If the value of resistance R becomes twice of its initial value then amplitude of current at resonance will be
(1) I02
Z= R2+(XL-XC)2; at resonance XL=XC Z=R, so I0= ER
R 2R (resonance unchanged): I= E2R= I02
Answer: (1)
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