Self-inductance
Changing current changes linked magnetic flux and induced emf.
Key knowledge
For a coil with fixed geometry and linear magnetic response, flux linkage NΦ = LI. With constant L, self-induced emf is −L dI/dt under the corresponding loop orientation.
Values and equations
NΦ = LI; ℰ = −L dI/dt
- N
- Number of equally linked turns
- Φ
- Flux per turn Wb
- L
- Self-inductance H
- I
- Coil current A
- ℰ
- Induced emf V
- t
- Time s
Conditions and scope
- Use total linked flux; NΦ presumes the same flux through each of N turns.
- Saturation, hysteresis, motion and frequency-dependent loss can invalidate a constant lumped L.
Sources · 1
References
Sources retain their recorded scope. A source link alone does not establish verification of every statement.
Evidence and review
Equations 14.9–14.10 and flux-linkage definition.
2026-10-10 · Constant linear self-inductance only; mutual coupling and nonlinear magnetic energy excluded.
Entry details
Permanent link to this entry ↗- Record identity
- physics-inductance
- Revision
- university-reference.1
- Structured reference record
- University reference · University core expansion