Question
A coil of inductance 0.50 H and resistance is connected to a 240 V50 Hz a.c. supply. What are the maximum current in the coil and the time lag between voltage maximum and current maximum?

3.5 ms

3.2 ms

3.0 ms

None of these
diffcult
Solution
3.2 ms
The maximum (peak) current in an LR circuit is given by
.
.
In LR circuit, the current lags behind the voltage by a phase angle , where
Putting the value of and R, we have
The time tag is given by
.
SIMILAR QUESTIONS
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