Science Common Sense

149 - Why do some substances float while others sink?

Imagine you have a big container of water. If you put something in the water, like a rock or a piece of wood, one of two things will happen: it will either sink to the bottom or float on top.

The reason for this is because of something called density. Density is how heavy something is compared to its size. If something is heavy for its size (like a rock), it will sink because it's denser than the water. But if something is light for its size (like a piece of wood), it will float because it's less dense than the water.

Think of it like a big game of "who's the lightest?" in the water. The things that are lightest (less dense) will float on top, and the things that are heaviest (more dense) will sink to the bottom.