Electromagnetic Induction
An electrical conductor that can be moved freely is placed between the N and S (magnetic) poles of a magnet as shown in the diagram. Then, a galvanometer is connected to the conductor to complete a circuit.
When the conductor is moved between the magnetic poles as shown in the diagram, the indicator of the galvanometer swings.
Thus, when the conductor is moved between the magnetic poles, the conductor crosses and cuts off the magnetic flux, which generates a current. For this reason, if the conductor is moved parallel to the magnetic flux, no current will be generated. Read more Principle of Electricity Generation