Why don’t you see lightning when you hear thunder?

If you hear thunder, the lightning has already happened. Whenever your hear distant thunder, you often see the lightning, too. A dazzling flash through the air. Pay careful attention. It takes a while before you hear the rumble of the thunder. Why is that?

Light travels faster than sound
Light and sound don’t travel at the same speed. The speed of light is about 300,000 kilometres per second. So the light – in the form of a flash of lightning – reaches you very quickly. Much faster than the sound (the thunder). Because the speed of sound is about 330 metres per second. Did you just see a flash of lightning? Then it’s just a matter of waiting... the thunder is on its way!