An a.c. source of 200 V , 50 Hz is connected across a 400 ohm resistor and an inductor of `3` H in series. Calculate impedance.

Explanation

`E_v = 200V`
Frequency `= v= 50 Hz`
Resistance `= R= 400Omega`
Inductance `= L=3/piH`
Reactance `= X_L = ?`
Impedance = Z= ?
Current = I = ?
(i)Reactance =` X_L`
`= 2pivL = 2pixx50xx3/pi = 300Omega`
(ii) Impedance `Z= sqrt((400)^2+(300)^2)`
`= sqrt(160000+90000)`
`Z = sqrt(250000)=500Omega`
(iii) Current (I) `=E_v/Z`
`I = 200/500 = 0.4 A`