Perpendicular how? There's more than one way to be perpendicular.
[math]{\nabla}{\cdot}{E}=\frac{\rho}{\epsilon_0}[/math]
[math]{\nabla}{\cdot}{B}=0[/math]
[math]{\nabla}{\times}{E}=-\frac{\partial{B}}{\partial{t}}[/math]
[math]{\nabla}{\times}{B}={\mu_0}{J}+{\mu_0}{\epsilon_0}{\frac{\partial{E}}{\partial{t}}}[/math]
Where [math]\rho[/math] is electric charge density, B is magnetic field, E is electric field, [math]\epsilon_0[/math] is permittivity of free space, [math]\mu_0[/math] is magnetic permeability of free space, J is current density, and t is time.