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Energy Density

A tornado is the most destructive natural storm. You might think that this also means that tornadoes are the strongest storms; that's not the case. In fact, a thunderstorm which produces a tornado can have 40,000 times more energy than a tornado! Then why are tornadoes so much more destructive than thunderstorms?

Tornadoes have a greater energy density than thunderstorms. They don't have as much energy but the energy they do have is packed into smaller spaces. Another way of thinking about this is with rocks and feathers. A bag of feathers might outweigh a rock, but put them both in water and the feathers will float while the rock sinks because the feathers are less dense. Tornadoes are so destructive because they strike a very small area.


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