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A `200muF` capacitor is in series with a `50Omega` resistor and is connected to a 220 V, 50 Hz ac source(i) What is the maximum current in the circuit (ii) What is the difference in time when the current and the voltage attain maximum values? |
Answer» Angular frequency of the source, `omega=2pif=2times3.14times50Hz` `C=200muF=2times10^-4F` Maximum current through the circuit , `I_0=V_0/(sqrt(R^2+1/(C^2omega^2)))` `=(sqrt2times220)/(sqrt((50)^2+1/((2times10^-4)^2times4times(3.14)^2times(50)^2)))` Now if`theta` is the phase angle then `tantheta=1/(omegaCR)=1/(2pifCR)=1/(2times3.14times50times2times10^-4times50)` =0.3185 or, `theta=tan^-1(0.3185)=17.67^@=(17.67timespi)/180rad` If the voltage and the current attain maximum value at a time difference of t, then `theta=omegat` or,`t=theta/omega=(17.67timespi)/(180times2pitimes50)=9.82times10^-4s` |
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