Follow your curiosity

What discovery has been shared with you?

FACTREE gives you something interesting to discover every day — and something worth talking about together.

Start with one fact. Explore it, go deeper, then follow whichever branch catches your imagination.

Choose subjects for a surprise

Exploring any topic

Begin your discovery

Your next discovery is one click away.

Choose one or more subjects above, or leave Any Topic selected and let curiosity decide.

Physics

Conservation of Energy

Quick fact

A bouncing ball never returns to its original height because some of its kinetic energy transforms into heat and sound, yet the total energy of the ball and ground system remains constant.

Why this is interesting

You’ve heard that energy is never lost, just transformed. But what does that actually mean for a bouncing ball, a burning log, or your own body?