How does political science differ from natural science and physical science?

Political science is a type of social science, which studies the state, government and politics. It is concerned with the theory and practice of politics, and with the analysis of different political systems and political behaviour.

Natural science is the study of the laws of nature - trying to understand what controls the natural world. This includes branches such as; Astronomy, Biology, Chemistry and Physics.

Physical science includes the branches of Natural science that involve the study of non-living things (as opposed to the Life sciences).