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प्रश्न
A conducting circular loop of area 1 mm2 is placed coplanarly with a long, straight wire at a distance of 20 cm from it. The straight wire carries an electric current which changes from 10 A to zero in 0.1 s. Find the average emf induced in the loop in 0.1 s.
उत्तर
Given:-
Area of the loop, A = 1 mm2
Current through the wire, i = 10 A
Separation between the wire and the loop, d = 20 cm
Time, dt = 0.1 s
The average emf induced in the loop is given by
\[e = \frac{d\phi}{dt}\]
\[ = \frac{BA}{dt} = \frac{\mu_0 i}{2\pi d} \times \frac{A}{dt}\]
\[ = \frac{4\pi \times {10}^{- 7} \times 10}{2\pi \times 2 \times {10}^{- 1}} \times \frac{{10}^{- 6}}{1 \times {10}^{- 1}}\]
\[ = 1 \times {10}^{- 10} V\]
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