Solving for the exact form of τ τ c a p ( ω ω ) or τ τ i n d ( ω ω ) requires solving Maxwell's equations on the grids, which for the general case can only be solved numerically. However, in an inductive grid the metal is continuous, and hence DC currents can exist. Considering the limiting case of ω ω → → 0 , the inductive grid must reflect the entire incident wave because of the boundary conditions for the electric field at the surface of a conductor. The relations derived above therefore show that a capacitive mesh will transmit the entire incident wave in this case.