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 known as Lenz's Law and 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