Fifteen uncoupled simple pendulums of monotonically increasing lengths dance together to produce visual traveling waves, standing waves, beating, and (seemingly) random motion. For more details...
See all National Geographic videos: video.nationalgeographic.com An annual tradition turns into disaster when onlookers are swept away by a tidal wave.
A ferocious tsunami spawned by one of the largest earthquakes on record slammed Japan's eastern coast on Friday, killing hundreds of people as it swept...
