PhysicsChapter 6: Alternating Current
Mutual Inductance
Mutual inductance
Definition
Mutual inductance is the phenomenon in which a changing current in one circuit induces an emf in a nearby coupled circuit.
Factors
Consider two nearby coils. A changing current `I₁` in coil 1 produces changing magnetic flux. Part of that changing flux links coil 2. An emf is therefore induced in coil 2: ε₂ = −M(dI₁/dt) where: `M` = mutual inductance. Similarly, under reciprocal ideal conditions: ε₁ = −M(dI₂/dt) Mutual inductance depends on factors such as: number of turns; coil geometry; separation; relative orientation; * magnetic medium/core.
Applications
Mutual induction is central to transformer action and inductive coupling.
Formula / Key Relation
**ε₂=−M(dI₁/dt) Unit: henry**
Exam preparation
Exam Focus
Quick revision
Revision Zone
Review the key facts, formulas and checks before you move on.Mutual Inductance
Sticky Notes · Quick Revision
Mutual induction:
- Coil 1 changing I
- → changing flux
- → emf in Coil 2
- `ε₂=-M dI₁/dt`
60-second revision
- Changing current in one coil can induce emf in another.
Did you understand this topic?
Your answer is saved with your learning record. It does not mark the topic as mastered.