A conducting circular loop is placed in a uniform magnetic field, B = 0.025 T with its plane perpendicular to the loop. The radius of the loop is made - Physics MCQ Physics | ExamTest.live

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A conducting circular loop is placed in a uniform magnetic field, B = 0.025 T with its plane perpendicular to the loop. The radius of the loop is made to shrink at a constant rate of 1 mms^{- 1} . The induced emf when the radius is 2 cm is:

A $2 μ V$
B $2 π μ V$
C $π μ V$
D $\frac{2}{π} μ V$

Solution & Step-by-step Explanation

Flux ϕ = B A = B (π r^{2}) . Induced EMF ϵ = \frac{d ϕ}{d t} = B π \frac{d}{d t} (r^{2}) = B π (2 r \frac{d r}{d t}) . Given: B = 0.025 T, r = 0.02 m, \frac{d r}{d t} = 1 0^{- 3} m/s . ϵ = 0.025 \times π \times 2 \times 0.02 \times 1 0^{- 3} ϵ = 0.05 \times 0.02 \times π \times 1 0^{- 3} = 0.001 π \times 1 0^{- 3} ϵ = 1 0^{- 6} π V = π μ V

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A conducting circular loop is placed in a uniform magnetic field, B = 0.025 T with its plane perpendicular to the loop. The radius of the loop is made to shrink at a constant rate of 1 mms^{- 1} . The induced emf when the radius is 2 cm is:

2 μ V

2 π μ V

π μ V

\frac{2}{π} μ V

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Magnetism Induced EMF Faraday's Law

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A conducting circular loop is placed in a uniform magnetic field, $B = 0.025 T$ with its plane perpendicular to the loop. The radius of the loop is made to shrink at a constant rate of $1 mms^{- 1}$ . The induced emf when the radius is $2 cm$ is:

Solution & Step-by-step Explanation

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Discussion

A conducting circular loop is placed in a uniform magnetic field, B=0.025 T with its plane perpendicular to the loop. The radius of the loop is made to shrink at a constant rate of 1 mms−1. The induced emf when the radius is 2 cm is:

Solution & Step-by-step Explanation

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Ready for a Full Test?

Discussion

A conducting circular loop is placed in a uniform magnetic field, $B = 0.025 T$ with its plane perpendicular to the loop. The radius of the loop is made to shrink at a constant rate of $1 mms^{- 1}$ . The induced emf when the radius is $2 cm$ is: