A derive 'X' is connected to an ac source `V=V_0sinomegat`.The variation of voltage ,current and power in one cycle is shown in the following graph:

Which of the curves A,B and C represent the voltage , current and the power consumed in the circuit ? Justify your answer .

Explanation

`C=q/V`
`thereforeq=CV=CV_0sinomegat[becauseV=V_0sinomegat]`
`therefore` Current , `I=(dt)/(dq)=d/(dt)(CV_0sinomegat)=omegaCV_0cosomegat`
`V_0/(1/(omegaC))cosomegat`
`thereforeI=V_0/X_Csin(omegat+pi/2)`or,`I=I_0sin(omegat+pi/2)`
In pure capacitive circuit current leads voltage by `pi/2`.