ELI5: Explain Like I'm 5

Naïve physics

Naive physics is the ideas we have in our heads about how things work in the physical world, even if we haven't studied physics. It's like a set of rules we use to understand how stuff moves, how objects interact with each other, and how they can change over time.

For example, if you drop a ball, you expect it to fall down to the ground because of gravity. That's part of your naive physics knowledge. If you push a block, you know it will move until something stops it.

Naive physics also includes our assumptions about how objects in the world hold together or break apart, how sound and light work, and why things don't just fly off into space. We naturally build up this knowledge over time, often without even realizing it.

Of course, sometimes our naive physics ideas aren't quite accurate. We might think a heavy object will fall faster than a light one, but in reality, they fall at the same speed. Or we might assume that objects need a push to keep moving, when in fact they keep moving on their own unless something stops them (like friction).

Overall, though, naive physics is a handy way to make sense of the world around us, even if we're not experts in the science of physics.