Question

A coil of 0.01 henry inductance and 1 ohm resistance is connected to 200 volt, 50 Hz ac supply. Find the impedance of the circuit and time lag between max. alternating voltage and current.

Answer 1

Here, `L = 0.01 H, R = 1 Omega, E_(v) = 200 V, v = 50 Hz, Z = ?, Delta t = ?`
`X_(L) = omega L = 2 pi v L = 2 xx 3.14 xx 50 xx 0.01 = 3.14 Omega`
`Z = sqrt(R^(2) + X_(L)^(2)) = sqrt(1^(2) + (3.14)^(2)) = sqrt(10.86) = 3.3 ohm`
`tan phi = (omega L)/(R ) = 3.14`
`phi = tan^(-1) (3.14) = 72^(@) = 72 xx (pi)/(180) rad`
Time lag, `Delta t = (phi)/(omega) = (72 xx pi)/(180 xx 2 pi xx 50) = (1)/(250) sec`