Question:
Two identical induction coils each of inductance $L$ joined in series are placed very close to each other such that the winding direction of one is exactly opposite to that of the other, what is net inductance?
Two identical induction coils each of inductance $L$ joined in series are placed very close to each other such that the winding direction of one is exactly opposite to that of the other, what is net inductance?
Updated On: Jul 2, 2022
- $L^{2}$
- $2L$
- $\frac{L}{2}$
- Zero
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The Correct Option is D
Solution and Explanation
When the two coils are joined in series such that the winding of one is opposite to the other, then the emf produced in first coil is $180^{\circ}$ out of phase of the emf produced in second coil. Thus, emf produced in first coil is negative and the emf produced in second coil is positive, so, net inductance is
$L=L_{1}+L_{2}=L+L$
$\Rightarrow L=-\frac{\phi}{i}+\frac{\phi}{i}=0$
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Concepts Used:
Electromagnetic Induction
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- When we place the conductor in a changing magnetic field.
- When the conductor constantly moves in a stationary field.
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The electromagnetic induction is mathematically represented as:-
e=N × d∅.dt
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- Φ = Magnetic flux (This is the amount of magnetic field present on the surface)
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