Voltage and magnetic fields are related through a phenomenon known as electromagnetic induction. This phenomenon was first discovered by Michael Faraday in the 19th century and is one of the fundamental principles of electromagnetism.
Electromagnetic induction states that a changing magnetic field can induce an electromotive force (EMF), also known as voltage, in a conductor. This EMF leads to the creation of an electric current if the conductor forms a closed loop. The magnitude of the induced voltage depends on the rate of change of the magnetic field and the number of turns in the conductor loop. Mathematically, electromagnetic induction is described by Faraday's law of electromagnetic induction.
Faraday's law of electromagnetic induction states that the induced electromotive force (voltage) in a closed loop is proportional to the negative rate of change of magnetic flux through the loop. The magnetic flux (
Φ
Φ) is the product of the magnetic field (
B) perpendicular to the loop and the area (
A) of the loop:
Φ
=
⋅
Φ=B⋅A
Mathematically, Faraday's law can be expressed as:
=
−
Φ
E=−
dt
dΦ
Where:
E is the induced electromotive force (voltage).
Φ
dt
dΦ
represents the rate of change of magnetic flux.
In summary, a changing magnetic field induces a voltage in a conductor, and this induced voltage can lead to the flow of an electric current if the conductor forms a closed loop. This relationship between voltage and magnetic fields is a fundamental aspect of electromagnetism and plays a crucial role in various technologies, including generators, transformers, and many electrical devices.