Question:
A disc of radius 0.1 m is rotating with a frequency 10 rev/s in a normal magnetic field of strength 0.1 T. Net induced emf is
A disc of radius 0.1 m is rotating with a frequency 10 rev/s in a normal magnetic field of strength 0.1 T. Net induced emf is
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A disc of radius 0.1 m is rotating with a frequency 10 rev/s in a normal magnetic field of strength 0.1 T. Net induced emf is
Updated On: Apr 15, 2026
- $2\pi\times10^{-2}V$
- $\pi\times10^{-2}V$
- $\frac{\pi}{2}\times10^{-2}V$
- None of these
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The Correct Option is B
Solution and Explanation
Step 1: Formula
$\epsilon = \frac{1}{2}B\omega r^2$.
Step 2: Values
$B = 0.1 \text{ T}, \omega = 2\pi f = 20\pi \text{ rad/s}, r = 0.1 \text{ m}$.
Step 3: Calculation
$\epsilon = \frac{1}{2} \times 0.1 \times 20\pi \times (0.1)^2 = \pi \times 10^{-2} \text{ V}$.
Final Answer: (B)
$\epsilon = \frac{1}{2}B\omega r^2$.
Step 2: Values
$B = 0.1 \text{ T}, \omega = 2\pi f = 20\pi \text{ rad/s}, r = 0.1 \text{ m}$.
Step 3: Calculation
$\epsilon = \frac{1}{2} \times 0.1 \times 20\pi \times (0.1)^2 = \pi \times 10^{-2} \text{ V}$.
Final Answer: (B)
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