We preserve the important events and people in our lives. The ceremonies of birth and birthdays, marriages and anniversaries, holidays and new houses are all recorded because they matter. Photographs are our personal story, a timeline of our lives filled with faces and places that we love.
It is a phenomenon of producing induced current in a coil by changing the magnetic feild around the coil is called Electromagnetic induction.
When magnetic feild is changed uniformly around a conductor an E.M.F is used inside the conductor which produces electric current.
Electromagnetic induction is the basic principle of electric generator.