A series LCR circuit with `R=20Omega,L=1.5H,andC=35muF` is connected to a variable frequency 200 V ac supply. When the frequency of the supply equals the natural frequency of the circuit, what is the average power transferred to the circuit in one complete cycle?

Explanation

Given : `R=20Omega,L=1.5H,C=35xx10^(-6)F,v_(rms)=200V,f=f_(0),barP=?`
At resonance Z = R
`therefore i_(rms)=(v_(rms))/(R)=(200)/(20)=10A`
Power factor of a series RLC at resonance `cosphi=1`
`therefore` Average power transferred to the circuit in one complete cycle,
`=i_(rms)v_(rms)cosphi`
`=10xx200xx1`
`=2000W`
`=2.0kW`