JEE Mains · Physics · STD 12 -6. Electromagnetic induction
A planar loop made of wire is rotating in a uniform magnetic field. At time \(t=0\), the plane of the loop is perpendicular to the magnetic field. If the loop is rotating about an axis passing through its plane with a period of \(10\) seconds, at which of the following times will the induced electromotive force (emf) be maximum and minimum, respectively?
- A \(2.5\; s\) and \(7.5 \;s\)
- B \(5.0\; s\) and \(7.5 \;s\)
- C \(5.0\; s\) and \(10.0 \;s\)
- D \(2.5\; s\) and \(5.0 \;s\)
Answer & Solution
Correct Answer
(D) \(2.5\; s\) and \(5.0 \;s\)
Step-by-step Solution
Detailed explanation
\(\operatorname{Fiux} \phi=\overline{B} \cdot \overline{A}=\mathbf{B A} \cos \theta=\mathbf{B A} \cos \omega t\) \(|\) Induced emf \(|=| \mathrm{e}|=| \frac{\mathrm{d} \phi}{\mathrm{dt}}|=| \mathrm{BA} \omega \sin \omega t |\) le \(|\) will be maximum at…
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