When one inductor coil is connected to a 20 V DC battery then it draws a steady - state current of 10 A . This inductor coil is connected across AC supply of rms voltage 10 V and one capacitor in series . It if found that current and vlotage are in same phase . What will be the rms current in the circuit ?

Explanation

In DC circuit let R be the resistance of inductor coil . Then
`R = (V)/(I)`
Here `V= 20 V, I = 10 A `
`:. R = (20 )/(10) = 2 Omega`
Now the inductor coil is connected across AC supply . So the reactance `(X_(L))` of the coil will also be effective . A capacitor is also connected in series with the coil and current and voltage are in phase.
`:. X_(C)= X_(L)`
Impedance of the circuit Z=R = 2 `omega`
`epsilon_("rms") = 10V `
`:.` rms current in the circuit will be
`I_("rms") = (epsilon_("rms"))/(Z) = (10)/(2) = 5 A `