Thunder from a lightning flash
A lightning flash heats the air around it very fast. The air pushes outward with a huge rumble, and that rumble is thunder.
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Examples
- A storm over your house at night
- Fireworks that boom after the bright burst
Key takeaways
- Thunder is the sound of air rushing outward from a lightning flash.
- Light travels faster than sound, so you see the flash before you hear the thunder.
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