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This article describes the inductance formula and how to calculate inductance. When electric current flows through the inductor, a magnetic field is produced around it. The strength of the magnetic field depends on the inductance, current, and number of turns in a coil.
The inductance is $$L = \frac{\lambda}{I} = \frac{N\Phi}{I} $$ where \$\lambda\$ is the flux linkage - the magnetic flux links N turns.
Faraday’s law of induction may be stated as follows: The induced emf ε in a coil is proportional to the negative of the rate of change of magnetic flux: B d dt ε Φ =− (10.1.3) For a coil that consists of N loops, the total induced emf would be N times as large: B d N dt ε Φ =− (10.1.4) 10-3
5 lis 2020 · Faraday’s law states that the EMF induced by a change in magnetic flux depends on the change in flux Δ, time Δt, and number of turns of coils. Faraday’s law of induction can be used to calculate the motional EMF when a change in magnetic flux is caused by a moving element in a system.
The self-inductance of a solenoid is \[L = \dfrac{\mu_0 N^2A}{l}(solenoid),\] where \(N\) is its number of turns in the solenoid, \(A\) is its cross-sectional area, \(l\) is its length, and \(\mu_0 = 4\pi \times 10^{-7} \, T \cdot m/A\) is the permeability of free space.
When current is turned on in a solenoid, a magnetic field is generated that tries to stop the solenoid from being turned on. This property is called inductance.
For example, in the demo shown in the freshmen E&M class, the big coil has self-inductance about L ≈ 2 H while the light bulb has resistance about R ≈ 100 Ω, hence a rather short the time constant τ ≈ 0.02 seconds. BTW, the H in L = 2 H stands for Henry, the MKSA unit of inductance named after American scientist Joseph Henry (1797–1878),
