Question

in an alternating current circuit the phase difference between current i and voltage is fie then the wattless component of current will be

Answer 1

wattless current is said to be component of that current, which doesn't consume any power in the circuit.

see figure, here phase difference between current and voltage is ϕ ,

then, Icosϕ along the voltage and Isinϕ perpendicular the voltage.

but Isinϕ doesn't produce any power in the circuit because phase angle between $Isin\phi$ and voltage is π/2.

hence, In an alternating current circuit the phase difference between current i and voltage is phi then wattless component of current will be $\bf{Isin\phi}$