Welcome to the world of physics.

Physics is, arguably, the branch of science that has the most obvious connections with everyday life, and offers explanations for much of what we take for granted.

While chemistry deals with changes in substances, and biology explains living things, the effects they explain aren't always so obvious, and they're often one step removed from everyday experience.

If you want to explain how to pry up a heavy rock, or why the sky is blue, you turn to physics.