In this course we will study how the universe works. Okay, I know that sounds like a grand plan; but, trust me, it is an accurate description of physics. Not only will we learn how large systems (the moon orbiting about the earth, for example) behave, but the same principles also govern how everyday objects such as baseballs and rockets move. It’s this universality of classical mechanics that is so amazing. In fact, this idea of having a single concept (or just a few) describe many different systems is at the core of physics.
          Physicists (and other scientists) search for fundamental principles. When a physicist (or physics student!) sees a problem they first ask themselves “what are the fundamental principles at work here?” I’m not going to claim that this is an easy thing to do. Many systems are very complicated and it takes some time determine what is going on. One must stay focused on the task of sorting out the fundamentals from the extraneous information.
          Why do we study classical mechanics first? Why not jump into the physics of black holes or quantum computers? Simply put mechanics is the study of motion. Since virtually all systems involve movement we first must understand how to describe motion and what causes it. Because motion is central to everything, you can play “six degrees of separation” with classical mechanics- every field of physics is, in some way, an offshoot of classical mechanics. For example, in order to understand how your computer’s processor functions you need to learn about condensed matter physics (the physics of solids and liquids) which is based upon quantum mechanics and thermodynamics (the physics of heat and energy). And, guess what? Those are directly related to classical mechanics. This is why we study classical mechanics first.
          Below I’ve sketched a “concept map” that shows some of the connections between various areas of physics. It is by no means complete; if it were, there would be many more connections. For example, one relatively new field of study is sonoluminescence where one can produce light from sound pulses. Also, chaos theory has been connected to nearly every area of physics (and many non-physics fields such as economics). If one wanted, you could even extend the map to connect with the other science and engineering fields.- e.g. condensed matter physics is intimately related to physical chemistry.

concept map of physics
          Okay, so what’s the message to get from this? The classical mechanics that we will study in this course can be thought of as the foundation of all areas of physics as well as most of the other science and engineering fields. We are truly about to begin our quest to figure out how the universe works. 

 

A Few Thoughts About Understanding
          Critical thinking and understanding on a conceptual level are complex skills that are not easily mastered, but are ones that can provide a lifetime of benefits. There are a couple points that I’d like to mention.

  • Understanding does not come quickly or easily. Don’t give up if you don’t know how to proceed when you first look at a problem. Keep at it.
  • Memorizing does not equal understanding. Just knowing the names of something or the equations, does not mean that you know what’s going on. Names and equations are important, but they are not the end goal, only on part of the bigger picture.