PCB Currents: How They Flow, How They React

11. Transformers

11.1. Magnetic Fields Revisited

In Chapter 1, I introduced the concept of a magnetic field around a conductor. When current flows along a conductor, a magnetic field is created around the conductor. The field has a force that is inversely proportional to the square of the distance away from the wire and a direction that can be found by the right-hand rule, which is illustrated in Figure 11-1.

Figure 11-1 A magnetic field exists around the direction of current. If you point the thumb on your right hand in the direction of the ...