Faraday's law is ∫ E dl = - ∂Ф/∂t if we take sqaure root on both sides, √∫ E dl = √- ∂Ф/∂t √∫ E dl = i √ ∂Ф/∂t Now the r.h.s has "i" in it. Does this mean anything? Having "i" in a equation means anything? I have seen "i" in schrodinger equation and dirac equation. As like those equations, does the above equation also has any meaning?