JEE Mains · Physics · STD 12 -Electromagnetic induction
- JEE Mains 2024
- Hard
- Numerical
A ceiling fan having 3 blades of length \(80 \mathrm{~cm}\) each is rotating with an angular velocity of \(1200\ \mathrm{rpm}\). The magnetic field of earth in that region is \(0.5 \ \mathrm{G}\) and angle of dip is \(30^{\circ}\). The emf induced across the blades is \(N \pi \times 10^{-5} \mathrm{~V}\). The value of \(\mathrm{N}\) is _______.
Pick an option to check your answer.
Answer & Solution
Correct Answer
(B) \(32\)
Step-by-step Solution
Detailed explanation
\( B_v=B \sin 30=\frac{1}{4} \times 10^{-4} \)
\( \omega=2 \pi \times f=\frac{2 \pi}{60} \times 1200 \mathrm{rad} / \mathrm{s} \)
\( \varepsilon=\frac{1}{2} B_V \omega \ell^2 \)
\( =32 \pi \times 10^{-5} \mathrm{~V}\)
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