Magnetic Fields

Magnetism

In this course, Professor Mohamed Anber (Durham University) explores magnetism. In the first mini-lecture, we discuss the magnetic fields of natural magnets and infinite wires carrying current. In the second mini-lecture we define the magnetic force and explore examples involving the magnetic force of one infinite wire on another. The third mini-lecture introduces magnetic flux in order to understand Faraday’s Law. In the fourth mini-lecture we turn towards an application of magnetism, the electric generator, and work through a calculation that gives us the electromotive force (EMF) of the electric generator. The fifth mini-lecture introduces a useful tool called the right hand rule that allows us to determine the direction of a magnetic field due to a wire carrying current, before introducing the principle of superposition and using these two new concepts in a variety of examples involving two infinite wires carrying current. The sixth and final mini-lecture goes over two demonstrations, the first involving natural magnets, and the second displaying Faraday’s Law.

Magnetic Fields

In this mini-lecture, we introduce the concept of magnetic fields. In particular. We consider: (i) natural magnets, where we see that like poles repel while opposite poles attract; (ii) magnetic field lines, which are always closed and describe the magnetic field strength depending on the density of lines; (iii) the magnetic field of an infinite wire carrying current; and (iv) the magnetic field lines of other current-carrying wires, such as a loop.