Why magnetic field deflects a charged particle.?

[Aladin]

Hello.
Sir My question is that:Why magnetic field deflects a charge particle or a charged particle experiences a force in a magnetic field?Ok
In electric field between two parallel plates a +ve charge particle deflects towards -ve plate when it is thrown perpandicularly.
But in magnetic field there is no any -ve or +ve plate then what thing in magnetic field deflects this charge?
thanks

 

[rbj]

fundamentally, the magnetic effect is the consequence of applying the effects of special relativity to the electrostatic field. there's a thought experiment, using two infinite, straight, and parallel lines of charge, that shows this equivalence, at least in this special case (so it's not a proof of the general case). instead of repeating myself, i have a post somewhere else that explains that special case to take a look at.