Physics is everything. We’re not saying that just because we’re diehard fans of the subject—it’s literally about every physical thing. Physics tries to come up with rules, principles, and laws to explain absolutely everything in the whole universe ever, using the scientific method, of course.
The official definition says that it’s the branch of science that deals with the nature and properties of matter and energy, and their motion through space and time, but that simple language hides how HUGE of a subject it is. Physics explains the smallest things we know exist—tiny particles like quarks—and the largest things—stars, galaxies, and the expansion of the universe itself.
We know. We know what some are thinking: if physics is about everything, then, surely, instead of doing a bunch of math, we could play video games. We like that kind of thinking. We could, definitely. However, even though physics even explains the workings of all game consoles, the math can be a little hairy, so that’s a lesson for another day.
The ultimate goal of physics is to come up with a Theory of Everything. One, single and elegant law or set of laws that explains why the entire universe behaves the way it does. That’s why physics includes such a wide range of topics: forces, motion, rotation, energy, electricity, waves, heat, engines, fluids, waves (including light and sound), optics, subatomic particles, astronomy, materials structure, aeronautics, and a million other things. (Time to inhale!)
If you think that explaining everything sounds like a difficult task, you wouldn’t be the only one. But we take baby-steps and get closer to completing that task with every passing year. The more we understand, the more we can do—like building an internet, making eye glasses, or creating a brain scanners. Thank you, physics.