
Here self inductances are in series but their mutual inductances are linked oppositely.
As the inductors connected are in series opposition, hence magnetic flux will be opposing each other. Therefore,
Leq=L1+L2−2M
JEE Main 2022 — Physics Electromagnetism
Two coils of self inductance L1 and L2 are connected in series combination having mutual inductance of the coils as M. The equivalent self inductance of the combination will be

Held on 26 Jun 2022 · Verified 6 Jul 2026.
L11+L21+M1
L1+L2−2M
L1+L2+M
L1+L2+2M
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