Wed. Week 11, May 7: Intro to Magnetism

Magnetism was today's topic of conversation. Permanent magnets are made up of elements that contain a large number of electrons alone in their orbitals. The unpaired electrons create a field that is similar to the  electric field created by a charge. This field is known as the magnetic field and has many important properties that relate to electric current and force.

The first exercise of the day was drawing up our predictions of the magnetic field for a bar magnet. The field lines extend from the north to south pole of the magnet and the magnetic flux through any closed surface is always zero.

We eventually came to the topic of how magnetic fields interact with moving charges. Since a moving charge exerts a magnetic field, it will interact with any external magnetic field, which will in turn apply a force on that moving charge. The resulting force is referred to as magnetic force and acts in the direction that is perpendicular to the directions of the charge's velocity and the external magnetic field. With this in mind, we deduced that a charge traveling at constant velocity with travel in a circular path within a uniform magnetic field.

After deriving several equations for magnetic force, we performed an experiment to find the value of the magnetic field for a bar of specific length, with a specific current running through it, moving at a specific acceleration.