# Why is magnetic field perpendicular to that plane?

Magnetic field is perpendicular to the plane containing direction of flow of current in a straight wire and radius vector.What I have been told is that,to explain lorentz force magnetic field was taken perpendicular to the direction of the plane containing radius vector and direction of flow of current.
Now if we talk about physical significance,what I had understood is that the direction of electric field gives the direction of the electrical component of electromagnetic waves but I couldn't relate magnetic field to magnetic component of electromagnetic wave.The magnetic field I mentioned above from starting is perpendicular to the plane but the magnetic field component of electromagnetic wave is not looking so.Can someone explain me?

Or am I opting a wrong idea of electromagnetic wave?

• In the general case electromagnetic waves are very complicated and they depend on the boundary conditions (i.e. the sources) in a very hard to calculate way (you would have to pay big bucks for software that actually does it right), so we like to avoid the most general case for teaching purposes. Your example with the wire loop in a plane is an "easy" case with high symmetry that can be calculated easily, so are free plane waves where the magnetic and the electric component are perpendicular to the wave vector. – CuriousOne Jul 11 '15 at 18:42
• @CuriousOne I didn't understand what you said.In other words of my question I was considering electromagnetic wave as a sinusoidal wave of electric and magnetic field perpendicular to each other.When we say that magnetic field travels in circular path around a current carrying wire,can we relate it to magnetic field of the electromagnetic wave.I got confused when I took electric field also. – Sikander Jul 11 '15 at 19:26