The current, which does not contribute to the power consumed in an AC circuit is called

Options

A. non-ideal current
B. wattless current
C. convectional current
D. inductance current

Answer

B

Explanation

Wattless current does not contribute to the mean rate of working of the circuit.
As, power factor `=("True power")/("Apparent power")=cosphi`
`=(R)/(sqrt(R^(2)+(X_(L)-X_(C))^(2)))`
`therefore` Power factor, `cosphi=(R)/(Z)`
In a non-inductive circuit, `X_(L)=X_(C)`
`therefore `Power factor`=cosphi=(R)/(sqrt(R^(2)))=(R)/(R)=1`
`therefore phi=0^(@)`
This is the maximum value of power factor. in a pure inductor or an ideal capacitor
`phi=90^(@)`
`therefore`Powe factor=`cosphi=cos90^(@)=0`
Average power consumed in a pure iniductor or ideal capacitor
`P =E_(V)*I_(V) cos90^(@)=`zero
Therefore, current through pure L or pure C, which consumes no power for its maintenance in the circuit is called ideal current or wattless current.