An alternating voltage of frequency `f` is applied across a series `LCR` circuit.Le `f_(r)` be the resonance frequency for the circuit.Will the curren

Monjur Alahi

An alternating voltage of frequency `f` is applied across a series `LCR` circuit.Le `f_(r)` be the resonance frequency for the circuit.Will the current in the circuit lag, lead or remain in phase with the applied voltage when (i)`f gt f_(r)`,(ii)`f lt f_(r)` ? Explain your answer in each case.


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Salim Ahmed Kawsar

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`X_(L)=2pifL` and `X_(C)=1/(2pifC)`
(i)When `f gt f_(r),X_(L)` is large and `X_(C)` is small.The circuit is induction current lags behind the applied voltage.
(ii)When `fltf_(r),X_(L)` is small and `X_(C)` is large.The circuit is capacitive the current leads the voltage in phase.

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