What is spherically symmetric field?

Discuss that potential is spherically symmetric for a point charge. Define eV, MeV and meV.

What is meant by the statement that the electric field of a point charge has spherical symmetry, whereas that f an electric dipole is cylindrically symmetrical?

What is spherical refracting surface? What do you mean by centre of curvature, radius of curvature, aperature and principal axis.

What is radial magnetic field ?