JEE Mains · Physics · STD 12 -7. Alternating current
An inductor stores 16 J of magnetic field energy and dissipates 32 W of thermal energy due to its resistance when an a.c. current of 2 A (rms) and frequency 50 Hz flows through it. The ratio of inductive reactance to its resistance is ___________. \((\pi=3.14)\)
- A 157
- B 314
- C 628
- D 100
Answer & Solution
Correct Answer
(B) 314
Step-by-step Solution
Detailed explanation
\(\frac{1}{2}Li_{ms}^{2}=16\Rightarrow L=8\) \(i^{2}R=32\Rightarrow R=8\) \(x_{L}=\omega L\Rightarrow2\times3.14\times50\times8\) \(\Rightarrow800\times3.14\) \(R=8\) \(\frac{x_{L}}{R}=314\)
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