Question

What produces the emf in an electric generator?
(Points : 3)
a coil rotating in a magnetic field to change its flux

an electric current in a coil that produces a torque on the coil to make it rotate

an electric battery

the repulsion between a positive charge and the north pole of a magnet

Answer 1

@IrishBoy123

Answer 2

I think it is A.

Answer 3

You would be correct. Because the magnetic lines of force cut the coils and that CHANGE in magnetic field, as seen by the coils, induces currents in the coils. Technically, the CHANGE is change in flux. Flux changes can occur if either the area is changing or magnetic field is changing (or both).