In a perfect conductor, the conductivity is infinite, so E=0 and any net charge resides on the surface.
a.Show that the magnetic field is constant ( ∂B/∂t=0 ), inside a perfect conductor.
b. Show that the magnetic flux through a perfectly conducting loop is constant.
A superconductor is a perfect conductor with the additional property that the (constant) B inside is in fact zero. (This is known as the Meissner effect.)
c. Show that the current in a superconductor is confined to the surface.