Faraday’s law is the driving force for electricity utilisation in industrial applications. In other words, electromagnetic induction is the principle on which the motors, transformers, generators, coils, and other electronic devices operate. It is based on the voltage generation in the conductor, proportional to the time-dependent change of magnetic field amplitude, frequency or direction.
The generated voltage for the solenoid coil is represented by electromotive force \( ε_{mf} \), which is calculated as follows:
\[ ε_{mf} = {\frac{μ.N.∆I.S}{l.∆t}} = {\frac{∆B.S}{∆t}}, where ∆B = {\frac{μ.N.∆I}{l}} \]
µ – permeability of yoke in the coil, if no yoke
is presented then the permeability of the vacuum can be used for the
calculation
N – number of turns of the coil
ΔI – change of the current flowing through the
coil
S – area (cross-section) of the coil
l – length of the coil
Δt – the time in which the change of the current
occurred