Faraday's Law Calculator

Calculate electromagnetic induction, EMF, and magnetic flux using Faraday's law

Calculate Electromagnetic Induction

Number of coil turns in the loop

Time period for change to occur

Change in magnetic flux through the coil

Faraday's Law Results

0.000000
V
Induced EMF
0.000000
Wb
Magnetic Flux
Faraday's Law: ε = -N × (dΦ/dt)
Number of turns: 1
Time interval: 0 s
EMF magnitude: 0.000e+0 V
Flux change rate: 0.000e+0 Wb/s
Lenz's law: EMF opposes flux change

Physics Analysis

Example Calculation

Coil in Changing Field

Coil area: 30 cm²

Number of turns: 10

Field change: 0.4 T

Time interval: 8 seconds

Calculation

Φ = B × A = 0.4 × (30 × 10⁻⁴) = 0.0012 Wb

ε = -N × (dΦ/dt)

ε = -10 × (0.0012/8)

ε = -0.0015 V

Key Formulas

1

ε = -N × (dΦ/dt)

Faraday's law with Lenz's law

EMF from flux change rate

2

Φ = B × A

Magnetic flux through area

Flux = field × area

3

ε = -N × A × (dB/dt)

EMF from field change

When area is constant

Units & Constants

EMF (ε)Volts (V)
Magnetic flux (Φ)Webers (Wb)
Magnetic field (B)Tesla (T)
1 Weber1 T⋅m²
1 Tesla1 Wb/m²

Understanding Faraday's Law

What is Electromagnetic Induction?

Electromagnetic induction is the phenomenon where a changing magnetic field induces an electric current in a conductor. This fundamental principle is the basis for electric generators, transformers, and many other electrical devices.

Lenz's Law

  • The induced current opposes the change that created it
  • Represented by the negative sign in Faraday's law
  • Conservation of energy principle in electromagnetic systems

Mathematical Foundation

ε = -N × (dΦ/dt)

Faraday's law of electromagnetic induction

ε:Induced EMF (electromotive force)
N:Number of turns in the coil
dΦ/dt:Rate of change of magnetic flux
Φ:Magnetic flux (Φ = B × A)

Note: The negative sign indicates that the induced EMF opposes the change in flux, following Lenz's law and energy conservation.

Electric Generators

Rotating coils in magnetic fields generate electricity. The changing flux through the coil induces EMF, converting mechanical energy to electrical energy.

Transformers

Changing current in primary coil creates changing magnetic flux, which induces voltage in secondary coil. Used to step voltage up or down in power systems.

Induction Motors

Rotating magnetic fields induce currents in rotor windings, creating torque. Most common type of AC motor in industrial applications.