JEE Mains · Physics · STD 12 -Alternating current
- JEE Mains 2022
- Medium
- MCQ
The equation of current in a purely inductive circuit is \(5 \sin \left(49 \pi t-30^{\circ}\right)\). If the inductance is \(30\,mH\) then the equation for the voltage across the inductor, will be.\(\left\{\right.\) Let \(\left.\pi=\frac{22}{7}\right\}\)
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Answer & Solution
Correct Answer
(D) \(23.1 \sin \left(49 \pi t+60^{\circ}\right)\)
Step-by-step Solution
Detailed explanation
\(v _{0}= i _{0} x _{ L }\)
\(= i _{0}( wL )\)
\(=(5)(49 \pi)\left(30 \times 10^{-3}\right)\)
\(=23.1\)
Voltage will lead current by \(90^{\circ}\).
\(\therefore V =23.1 \sin \left(49 \pi t +60^{\circ}\right)\)
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