A coil of negligible resistance is connected in series with 90 resistor across 120 V, 60 Hz supply. A voltmeter reads 36 V across resistance. Inductance of the coil is :
(2) 0.76 H
I = VRR = 3690 = 0.4 A
V2 = VR2 + VL2 (series L–R)
VL = 1202 - 362 = 13104 114.5 V
XL = VLI = 114.50.4 286
L = XL2 f = 2862 60 = 286377 0.76 H
Answer: (2)
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