self inductance definition

Question

Self-induced emf in coil ε = -L (dI/dt). L depends on?

RankGuru · Accepted Answer

1. **Definition**: Self-inductance ($L$) is the inertia of an electrical circuit against changes in current.
2. **Coil Properties**: Like capacitance, $L$ is a purely geometric and material property of the component itself.
3. **Dependencies**:
   - **Cross-section area** ($A$)
   - **Length** ($l$)
   - **Number of turns** ($N$): $L \propto N^2$.
   - **Magnetic Permeability** ($\mu$): Presence of a magnetic core increases $L$.
4. **Formula for Solenoid**: $L = \frac{\mu_0 \mu_r N^2 A}{l}$. It does not depend on the current or applied voltage.

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self inductance definition

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