Electromagnetic Induction - Coil and Magnet

Electromagnetic induction is the process by which an electromagnetic field is generated through changes in magnetic flux. A specific case of this phenomenon is mutual inductance, which describes how Faraday’s law of induction operates between two devices. For example, in a system where a primary coil transmits energy to a secondary coil, changes in the current within the primary coil induce a voltage in the secondary coil. When the devices remain stationary, the magnetic flux only changes when the current in the primary coil fluctuates. This is why induction occurs in the secondary coil when an alternating voltage (AC) is applied to the primary winding, as the continuously changing current creates a varying magnetic field. However, if direct current (DC) is used, the voltage in the secondary winding is observed only for a brief moment, during the initial change in current, such as when a switch is activated.