Verified Solution • 2025–26 Session moderate

QPages 330-331: Q15: HC Verma: Concepts of Physics - Volume 2 Alternating Current Pages 330-331: Q15 Solution: Consider the situation of the previous problem. Find the…

⚠️ Common Exam Traps & Conceptual Pitfalls

Students often plug the peak voltage or current into $\frac12 C V^2$ or $\frac12 L I^2$ and call it the average stored energy, forgetting that the energy oscillates with $sin^2$ and the correct average uses RMS values: $\langle U_C\rangle=\frac12 C V_{\rm rms}^2$, $\langle U_L\rangle=\frac12 L I_{\rm rms}^2$. Using peak values overestimates the average by a factor of two.

Consider the situation of the previous problem. Find the average electric field energy stored in the capacitor and the average magnetic field energy stored in the coil.

Step-by-Step Verified Solution

**Answer:** Capacitor energy =25 mJ= 25 \, \text{mJ}, Inductor energy =5 mJ= 5 \, \text{mJ}. **Step-by-Step Explanation:** Using values from Q14: Irms=0.1 AI_{rms} = 0.1 \, \text{A}, VC,rms=50 VV_{C,rms} = 50 \, \text{V}. Energy in capacitor =12CVC,rms2=0.5×20×10−6×502=25 mJ= \frac{1}{2} C V_{C,rms}^2 = 0.5 \times 20 \times 10^{-6} \times 50^2 = 25 \, \text{mJ}. Energy in inductor =12LIrms2=0.5×1×0.12=5 mJ= \frac{1}{2} L I_{rms}^2 = 0.5 \times 1 \times 0.1^2 = 5 \, \text{mJ} [citation:4].

All Questions in this Chapter

QPage 329: Q1 QPage 329: Q2 QPage 329: Q3 QPage 329: Q4 QPage 329: Q5 QPage 329: Q6 QPage 329: Q7 QPage 329: Q8 QPage 329: Q9 QPage 329: Q10 QPage 329: Q11 QPages 328-329: Q1 QPages 328-329: Q2 QPages 328-329: Q3 QPages 328-329: Q4 QPages 328-329: Q5 QPages 328-329: Q6 QPages 328-329: Q7 QPages 328-329: Q8 QPages 328-329: Q9 QPages 328-329: Q10 QPages 328-329: Q11 QPages 328-329: Q12 QPages 328-329: Q13 QPages 328-329: Q14 QPages 329-330: Q1 QPages 329-330: Q2 QPages 329-330: Q3 QPages 329-330: Q4 QPages 329-330: Q5 QPages 329-330: Q6 QPages 329-330: Q7 QPages 330-331: Q1 QPages 330-331: Q2 QPages 330-331: Q3 QPages 330-331: Q4 QPages 330-331: Q5 QPages 330-331: Q6 QPages 330-331: Q7 QPages 330-331: Q8 QPages 330-331: Q9 QPages 330-331: Q10 QPages 330-331: Q11 QPages 330-331: Q12 QPages 330-331: Q13 QPages 330-331: Q14 QPages 330-331: Q15 QPages 330-331: Q16 QPages 330-331: Q17 QPages 330-331: Q18 QPages 330-331: Q19

Related Learning Resources & Exam Preparation

Chapter Practice Bank
Practice all topic-wise questions from Alternating Current
Reference Textbook Solutions
Explore complete chapter exercises for HC Verma: Concepts of Physics - Volume 2
Competitive PYQ Question Bank
Browse year-wise authentic previous years' questions with solutions
Authentic CBT Mock Tests
Simulate official exam environment with live timer and percentile scoring