What are the four Formulae of electromagnetism?
The physicist James Clerk Maxwell, in the 19th century, based his description of electromagnetic fields on these four equations, which express experimental laws. … The four Maxwell equations, corresponding to the four statements above, are: (1) div D = ρ, (2) div B = 0, (3) curl E = -dB/dt, and (4) curl H = dD/dt + J.