The physics of the Universe appears to be dominated by the effects of four fundamental forces: gravity, electromagnetism, and weak and strong nuclear forces. These control how matter, energy, space, and time interact to produce our physical world. All other forces, such as the force you exert in standing up, are ultimately derived from these fundamental forces.We have direct daily experience with two of these forces: gravity and electromagnetism. Consider, for example, the everyday sight of a person sitting on a chair. The force holding the person on the chair is gravitational, while that gravitational force is balanced by material forces that “push up” to keep the individual in place, and these forces are the direct result of electromagnetic forces on the nanoscale. On a larger stage, gravity holds the celestial bodies in their orbits, while we see the Universe by the electromagnetic radiation (light, for example) with which it is filled. The electromagnetic force also makes possible the advanced technology that forms much of the basis for our civilization. Televisions, computers, smartphones, microwave ovens – even the humble light bulb is made possible by control of electromagnetism. The average physics major will spend more time understanding and applying the concept of electromagnetic force than he or she will spend studying any other type of force.The classical (i.e., non-quantum) theory of electromagnetism was first published by James Clerk Maxwell in his 1873 textbook “A Treatise on Electricity and Magnetism.” The work that ultimately led to Maxwell’s electromagnetism equations was carried out by a host of scientists during the 19th Century and is still considered one of the triumphs of classical physics. Maxwell’s description of electromagnetism, which demonstrates that electricity and magnetism are different aspects of a unified electromagnetic field, holds true today. In fact, Maxwell’s equations are consistent with relativity, which was not theorized until 30 years after Maxwell completed his equations.In this course, we will first learn about waves and oscillations in extended objects using the classical mechanics we learned inPHYS101. We will also establish the sources and laws that govern static electricity and magnetism. A brief look at electrical measurements and circuits will help us understand how electromagnetic effects are observed, measured, and applied. We will then see how Maxwell’s equations unify electric and magnetic effects and how the solutions to Maxwell’s equations describe electromagnetic radiation, which will serve as the basis for understanding all electromagnetic radiation, from very low frequency radiation emitted by power transmission lines to the most powerful astrophysical gamma rays. We will briefly study optics, using practical models largely consistent with the predictions of Maxwell’s equations, but easier to use. Finally, we will give a brief overview of Einstein’s theory of special relativity. A basic knowledge of calculus (MA101) will be assumed, but you will need to know the principles covered inMA102(a co-requisite for this course) as well.This course will require you to complete a number of problems. Unlike mechanics, most of the phenomena encountered in the field of electromagnetism are not found in everyday experience—at least, not in a form that makes the actual nature of the phenomena clear. As a result, learning electromagnetism involves developing intuition about a rather unintuitive area of physics. In the end, developing physical intuition is less about getting a right answer than it is about getting a wrong answer and then understanding why it was wrong. In an ideal situation, this course would require you to both work out problems concerning the phenomena and observe various important phenomena in the laboratory. However, because this is an online course, we do not have the luxury of lab sessions. (We have, however, included a number of interactive demonstrations.) To compensate for this, when you approach a problem, try to work out the size of those quantities that clarify the basic nature of the question proposed. Thinking of these numbers as data from an ideal laboratory will help you develop a sense of how electromagnetism works—a sense that most people do not get from the mathematical description of the physics.
Days of the Week:
Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday
- Level of Difficulty: All Levels
- Size: One-on-One
- Cost: Free
- Institution: Saylor
- Topics: Calculus, Physics