Faraday's Law
Contents
Key Stage 5
Meaning
Faraday's law of electromagnetic induction states that the induced emf in a circuit is equal to the rate of change of magnetic flux linkage through the circuit.
About Faraday's Law of Electromagnetic Induction
- Faraday's Law is fundamental in the operation of generators, transformers, and various electromagnetic devices.
- Magnetic flux linkage is defined as the product of the number of turns in the coil and the magnetic flux through the coil.
- Due to the law of conservation of energy the induced emf opposes the change in magnetic flux which is included in the formula representing Faraday's Law with a negative sign.
Formulae
Faraday's Law is stated mathematically as:
- \(\varepsilon=-\frac{\Delta\Phi}{\Delta t}\)
Where,
- \(\varepsilon\) is the electromotive force
- Φ is the magnetic flux
- t is the time.
The negative sign in the equation represents Lenz's Law, indicating that the induced emf opposes the change in magnetic flux.
Additionally Φ is given by:
- Φ=𝐵𝐴cos𝜃
Where:
- 𝐵 is the magnetic field strength
- 𝐴 is the area of the coil
- 𝜃 is the angle between the field and the normal of the area