An induced electromotive force in any closed circuit is equal to the negative of the time rate of change of the magnetic flux enclosed by the circuit

An induced electromotive force in any closed circuit is equal to the negative of the time rate of change of the magnetic flux enclosed by the circuit.
The shell – a bullet is held in an armature that can conduct electricity, which is then placed between two metal rails. A huge electric current is then passed through the rails, which generates magnetic fields that propels the armature forwards at a great velocity, refer to figure. The shell when it detaches from the armature, can reach up to seven times the speed of sound.
Electromagnetic induction is an incredibly useful phenomenon with a wide variety of applications. Faraday’s discovery of electromagnetic induction gives rise to countless technological industrial, technological, medical applications.