MCQ
A sinusoidal ac current flows through a resistor of resistance $R$. If the peak current is $I_p$, then the power dissipated is
- A$I_p^2 R \cos \theta$
- ✓$\frac{1}{2} I_p^2 R$
- C$\frac{4}{\pi} I_p^2 R$
- D$\frac{1}{\pi} I_p^2 R$
✓
Answer
Correct option: B.
$\frac{1}{2} I_p^2 R$
(b) Power $=I^2 R=\left(\frac{I_p}{\sqrt{2}}\right)^2 R=\frac{I_p^2 R}{2}$
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