Question:
A conducting circular loop is placed in a uniform magnetic field of 0.04T with its plane perpendicular to the magnetic field. The radius of the loop starts shrinking at 2mm s⁻1. The induced emf in the loop when the radius is 2cm is:
A conducting circular loop is placed in a uniform magnetic field of 0.04T with its plane perpendicular to the magnetic field. The radius of the loop starts shrinking at 2mm s⁻1. The induced emf in the loop when the radius is 2cm is:
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For shrinking loop: E=2π Br(dr)/(dt).
Updated On: Mar 20, 2026
- \(4.8\,\pi\,\mu\text{V}\)
- \(0.8\,\pi\,\mu\text{V}\)
- \(8\,\pi\,\mu\text{V}\)
- 16πμV
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The Correct Option is A
Solution and Explanation
Step 1: Magnetic flux: Φ=BA=π Br²
Step 2: Induced emf: E=|(dΦ)/(dt)|=2π Br(dr)/(dt)
Step 3: Substituting values: E=2π(0.04)(0.02)(2×10⁻3) =4.8πμV
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