Maxwells equations

• There are four Maxwell's equations (simplified in the following): "Div E = Rho/ Epsion0" explains that the source of an electric field is electrical charge; "Div B = 0" explains that magnetic charges do not exist; "Curl E = -dB/dt" relates an electrical field to a time varying magnetic field; and "Curl B = Mu0 x J" relates a spatially varying magnetic field to a current. Each of these equations are fundamental properties of electromagnetism, and hence are relevant to magnets passing through current loops.
  
  

Magnets and Magnetic Fields

• A permanent magnet is defined as a material that is capable of producing a spontaneous magnetic field. Permanent magnets have an intrinsic magnetic field, which has a set direction that is defined by its "north" and "south" poles. Outside of the magnet, the magnetic field decays with distance.
  
  

Wire Loop

• A wire loop is a short-circuited set of wire. The fact that it is short-circuited implies that no batteries or power supplies are connected to it, and thus no current flows through the wire loop under normal circumstances.
  
  

Faraday's Law

• Faraday's law explains what happens when a permanent magnet is passed through a current loop. In words, Faraday's law states that "a change in magnetic field will produce an electric field." When a permanent magnet is passed through a wire loop, it sees a brief change in magnetic field, and this generates an electric field. An electric field will accelerate electrons within the wire loop, hence creating a short-lived current.