Engineering Board Exam Reviewer · RL Circuits · hard
A coil draws 2 A from a 120 V, 60 Hz source, and the current lags the voltage by 60°. Find the inductance of the coil.
- 79.6 mH
- 138 mH
- 159 mH
- 866 mH
Answer
B. 138 mH
Solution
|Z|=120/2=60, . XL=|Z| 60°=52, . L=XL/2π f=52/2π(60)=138 mH.
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