Question

What is electromagnetic induction?

Answer 1

Electromagnetic induction is a process by which a magnetized or electrically charged object produces magnetism, an electric charge, or an electro-motive force (emf) in another object without being in contact with it.


An electro-motive force occurs in an electric conductor that is in a changing magnetic field, i.e. it is either (1) in motion relative to a magnet or (2) in a changing magnetic field produced by a changing electric current. For example, an electric generator produces a current because of electromagnetic induction.

Answer 2

Electromagnetic or magnetic induction is the production of an electromotive force across an electrical conductor in a changing magnetic field. 
Today, electromagnetic induction is used to power many electrical devices. One of the most widely known uses is in electrical generators (such as hydroelectric dams) where mechanical power is used to move a magnetic field past coils of wire to generate voltage.