MAGNETIC FLUX
Electromotive force can be created by the motion of a conducting wire through a
magnetic field, but there is another way to generate an emf from a magnetic field.
Faraday’s discovery found that a current is induced when the magnitude of the
magnetic field passing through the coil or loop of wire changes. Magnetic flux
helps us define what that amount of field passing into the loop means.
Imagine holding a loop of wire in front of a fan as shown:
The amount of air that flows through the loop depends on the area of the loop as
well as its orientation (tilt angle θ).