foreveryoung writes:
How do the magnetic and electrical sources exert a force an object that they are not in contact with? There has to be a medium in between them in order for one to exert a force on the other.
There are various levels of answers to this question, depending on how accurately you want the phenomena described or what principles you would prefer to understand it in terms of.
However, basically, electric and magnetic fields never exert a force on an object they are not in contact with, the must first reach the object they are going to influence. They do so by travelling at the speed of light from the source object which creates them.