What are eddy currents?

Eddy currents are indeed currents that are induced within conductors due to changing magnetic fields. When a conductor experiences a change in the magnetic field around it, such as when it is in motion relative to a magnetic field, circular loops of electrical current can form inside the conductor. These currents create their own magnetic fields and can lead to energy losses through heat due to resistance in the material. This phenomenon is utilized in various applications, such as induction heating and braking systems in trains.

In this context, it is important to differentiate eddy currents from other types of currents. For example, currents flowing in open circuits would not be influenced significantly by a magnetic field in the same way that eddy currents are. Moreover, while liquid metals can conduct electricity and may also experience currents, this is not a defining characteristic of eddy currents, which can occur in solid conductors as well. Lastly, eddy currents are not constant; they vary depending on changes in the magnetic field and the conductivity of the material in which they are induced.