Bubble (physics)

Okay kiddo, have you ever seen bubbles before? Like when you blow soap bubbles or see them in your drink? Those are all examples of bubbles.

Now, bubbles are made up of air or gas trapped inside a thin layer of some kind of liquid. The liquid can be soap (for soap bubbles), water (for bubbles in drinks), or any other liquid.

When you blow a soap bubble, for example, your breath contains air (which is a gas) and when it comes out of your mouth it goes into the liquid soap. The liquid soap surrounds the air and creates a thin layer around it.

Now, here's something really cool. The soap in the bubble is attracted to other soap molecules in the liquid, but not to air molecules. So, the soap molecules on the edge of the bubble stick together and create a kind of wall that keeps the air inside. That's why bubbles usually have a spherical shape - the soap wall is pulling in all directions, making the bubble as small and round as possible while still containing the air inside.

So, that's what a bubble is and how it's made. It's just trapped air surrounded by a thin layer of liquid that's held together by the attraction between molecules.