A Guide to How Physics Works and How to Have Fun With It
written by: William Springer
• edited by: Amanda Grove
• updated: 1/19/2015
Physics has a reputation for being something that smart people do, but actually we all use it every day. Learn some of the fundamentals behind the science that attempts to explain the universe.
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Getting Started With Physics
Physics is the study of matter and energy, and how they interact; it includes such things as heat, light, electricity, magnetism, sound... everything about how the natural world works. It has been said that biology is applied chemistry, while chemistry is applied physics. Simply put, physics is how we explain the world around us; it allows us to use math to make predictions about how objects will behave.
Part of the fun in physics is finding out how interesting things work. For example, you may have seen waves moving through the ocean, but did you know that a wave is actually moving energy rather than moving water? You know that a small child can balance a large man on a seesaw if they sit in the right places, but can you calculate where they need to sit? If you drop an egg off the top of the Empire State Building (you shouldn't do this, by the way!), how long will it take to hit the ground, and how fast will it be going?
Oh, and if you don't believe me about the waves? Tape a piece of rope, hold one end of it, and give the other end to a friend. Move your end up and down; you'll see a number of waves move through the rope toward your friend, but you'll still be holding your end; the rope will not have moved away from you!
Many video games these days involve physics, either directly (games that involve building bridges or otherwise directly working with gravity and other physical phenomena) or indirectly (any game engine that provides realistic physics, such as accurately simulated car crashes or photorealistic rendering). Programming realistic physics into the game makes it more like the real world, allowing us to adapt our actual experiences to the game world.
What fun is a guide to the fundamentals of physics if it doesn't show you how to do some cool experiments? Unlike chemistry and biology, it's easy to do physics experiments with materials you're likely to have sitting around the house; in fact, many physics experiments are actually thought experiments, where you don't need anything except your mind! If you're in the mood to get some new toys, though, it might help to have a good stopwatch.
When experimenting, they key is repeatability: keep track of everything that you do (and measure carefully) so that if you repeat the experiment, you'll get the same results. Plus, careful notes will make it much easier to get the maximum range with your trebuchet.
Even though people have been making important physics discoveries for thousands of years, there is still a lot that we don't know. These days, much research is focused on very big and very small things, from the entire universe (and how it got started) down to tiny subatomic particles (and where the missing ones are hiding). In some cases, physicists are able to deduce the existence of a new particle from the behavior of other particles, but may need to wait for better equipment before they can actually find them!
Some branches of physics - quantum physics, for example - require math that is very complicated. For the most part, however, you won't need anything more advanced than algebra and calculus. Algebra is all about solving for an unknown, while calculus lets you calculate rates of change; between them, they cover most of what you need. In college, you may even have a choice between taking algebra-based physics or calculus-based physics!
Naturally, learning physics involves learning physical laws, such as Newton's laws. These are theories (ways to explain how the world works) that we're very confident in, because they have been tested many times over the years. Of course, these days, experiments may also involve running computer simulations, so physicists may also need to be computer programmers! Once you've learned enough about the fundamentals of physics, you can go out there and make the next great discovery!