Alex’s Applied Physics
For the past few months, I’ve been learning physics from this book. I’ve found a couple things for which physics is really fun.
- Rocket: Using physics to simulate the travel of a rocket in a zero-gravity vacuum. This is relatively easy; in fact, there are a few different levels of complexity:
- Fuel-less engine. A fuel-less engine is the easiest thing to simulate. Basically, the engine has an unlimited supply of zero-mass fuel. The engine has a certain acceleration (e.g. 50m/s²), and you just put it at the origin and accelerate it around. It’s kind of fun.
- Limited fuel. An engine with limited fuel is a bit harder to simulate. The ship has a certain mass of fuel, in addition to its own mass. You pick a ‘force density’ (measured it Ns/Kg) for the fuel (I went for 0.4 Ns/Kg, the density of RP1/LOX fuel, a standard fuel in modern and historical rockets.) and, as the ship uses force to accelerate, its mass decreases. If the fuel mass runs out, the ship just keeps going in the direction it was heading.
- Bouncing ball: Basically, you have a ball in a box in zero-G. The ball rebounds perfectly; toss it at the wall and see what happens!