JEE Mains · Physics · STD 12 -6. Electromagnetic induction
A conducting circular loop is rotated about its diameter at a constant angular speed of 100 rad/s in a magnetic field of 0.5 T perpendicular to the axis of rotation. When the loop is rotated by 30° from the horizontal position, the induced EMF is 15.4 mV. The radius of the loop is ________ mm. (Take \( \pi=22/7 \))
- A 7
- B 14
- C 21
- D 28
Answer & Solution
Correct Answer
(B) 14
Step-by-step Solution
Detailed explanation
\(E = B \omega A \sin \omega t\) \(15.4 \times 10^{-3}=\frac{1}{2} \times 100 \times \frac{22}{7} r ^2 \times \frac{1}{2}\) \(r =\sqrt{\frac{15.4 \times 28 \times 10^{-5}}{22}}\) R=14mm
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