right hand rule question: I am trying to explain why 2 wires with current in the same direction will attract each other. If I say that I is going toward the top of the page. then when I apply the RH rule for the current carrying wire I get that B is going into the page to the Right of the wire, and out of the page to the left of the wire. So my question is which direction for B will I use to calculate the direction of force on the wire?

Question

right hand rule question:  I am trying to explain why 2 wires with current in the same direction will attract each other.  If I say that I is going toward the top of the page. then when I apply the RH rule for the current carrying wire I get that B is going into the page to the Right of the wire, and out of the page to the left of the wire.  So my question is which direction for B will I use to calculate the direction of force on the wire?

anonymous · Answer

Also why do we consider light to be a form of electromagnetic radiation if photons have no charge?

fwizbang · Answer

The answer to your first question depend on where the second wire is located relative to the first. To calculate the force on the second wire, use the field(produced by the first wire) at the location of the second wire, and vice versa.

Loosely speaking, Charge measures the strength of the interaction between objects an the electro-magnetic fields.  Electromagnetic fields don't interact with other electromagnetic fields, hence the objects that make up electromagnetic fields, photons, must not be charged.