JEE MainPhysicsAlternating CurrentMCQ+4 / −1
An inductance coil has a reactance of 100 . When an AC signal of frequency 1000 Hz is applied to the coil, the applied voltage leads the current by 45o. The self-inductance of the coil is
- A6.7 10–7 H
- B1.1 10–1 H
- C5.5 10–5 H
- D1.1 10–2 H
View written solutionFree
Correct answer: D
-
Interpret the given data
The coil is not purely inductive, because the applied voltage leads the current by instead of .
So the coil has:
- resistance
- inductive reactance
- phase angle
-
Use the phase angle relation for an - circuit
For a series - circuit,
Given ,
Since ,
This confirms the resistive part, but for inductance we only need and frequency.
-
Use the inductive reactance formula
Given:
Therefore,
Substitute values:
-
Match with the given options
The calculated value is approximately
Among the options, the nearest is:
- D:
-
Conclusion
The intended answer is Option D.
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