Principles of The Theory of Heat

Physics is the fundamental science. It explains how the universe behaves at every scale, from the subatomic to the extragalactic. It describes the most basic objects and forces and how they interact. Its laws tell us how the planets move, where light comes from, what keeps birds aloft, why a magnet attracts and also repels, and when a falling object will hit the ground, and it gives answers to countless other questions about how the world works.