Electromagnetic induction is the process by which a changing magnetic field induces an electromotive force (EMF) or voltage in a closed circuit. This phenomenon is described by Faraday's law of electromagnetic induction. The magnitude of the induced EMF can be calculated using the following formula:
=
−
Δ
Φ
Δ
E=−N
Δt
ΔΦ
Where:
E is the induced electromotive force (EMF) in volts (V).
N is the number of turns in the coil or the number of loops in the circuit.
Δ
Φ
ΔΦ is the change in magnetic flux through the coil in webers (Wb).
Δ
Δt is the change in time over which the magnetic flux changes, in seconds (s).
Magnetic flux (
Φ
Φ) is given by:
Φ
=
⋅
⋅
cos
(
)
Φ=B⋅A⋅cos(θ)
Where:
B is the magnetic field strength in teslas (T).
A is the area of the loop perpendicular to the magnetic field in square meters (m²).
θ is the angle between the magnetic field direction and the normal to the loop's surface.
When the magnetic field, the number of turns in the coil, or the area of the loop changes over time, the magnetic flux changes, leading to the induction of an EMF in the circuit.
Remember that the negative sign in the formula indicates the direction of the induced current according to Lenz's law, which states that the direction of the induced current will oppose the change that produced it.
This formula is a simplified representation and doesn't account for factors like resistance, self-inductance, or mutual inductance between multiple coils. For more complex setups, these factors might need to be considered for accurate calculations.