There are two coils A and B seperated by some distance. If a current of 2A flows through A, a magnetic flux of 10-2 Wb passes through B (no current through B). If no current passes through - Physics

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Short Note

There are two coils A and B seperated by some distance. If a current of 2A flows through A, a magnetic flux of 10-2 Wb passes through B (no current through B). If no current passes through A and a current of 1A passes through B, what is the flux through A?

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Solution

Let IA current is passing through coil A having mutual inductance MAB with respect to coil B

NA = number of turns in coil A

NB = number of turns in coil B

`phi_A` = flux linked with coil A due to coil B

`phi_B` = flux linked with coil B due to coil A

MBA = Mutual inductance of coil B with respect to coil A

Then, Total flux through B = M2 Φ2 = MBAI1

10–2 = MBA × 2

MBA = `10^-2/2` = 5 mH

Now total flux through A = MA ΦA = MBAI2  ......[∵ MBA = MBA]

= 5 mH × 1 Wb

= 5 m Wb

  Is there an error in this question or solution?
Chapter 6: Electromagnetic Induction - MCQ I [Page 37]

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NCERT Exemplar Physics Class 12
Chapter 6 Electromagnetic Induction
MCQ I | Q 6.21 | Page 37

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