This is an image of lightning.
Click on image for full size
Photograph provided courtesy of Steve Albers
Sound Waves vs. Light Waves
You see a flash of lightning across the night sky. Five seconds later,
your hear the rumble of thunder. If lightning and thunder come from the
same source, then why don't they occur at the same time?
Actually, they do occur at the same time. The difference is
due to the way sound and light travel. Light travels
extremely fast. In fact, it is faster than anything
else. Sound travels pretty slow. That is why we can
see light in an instant, but it takes a while to hear thunder.
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