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Question
Answer the following question.
What is the phase difference between the voltages across the inductor and the capacitor at resonance in the LCR circuit?
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Solution
It can be observed from the phasor diagram that the voltage across the inductor leads the current by `pi/2` and that along the capacitor leads the current by `pi/2`, so in every situation, the phase difference between the inductor and the capacitor is `pi`.
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(i) Find the value of the phase difference between the current and the voltage in the series LCR circuit shown below. Which one leads in phase : current or voltage ?
(ii) Without making any other change, find the value of the additional capacitor C1, to be connected in parallel with the capacitor C, in order to make the power factor of the circuit unity.

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