Hot-air balloons float because the air inside the balloon is less dense than the outside air.
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Energy Density
A tornado is the most intense force in nature. That doesn't mean it's
the most powerful. In fact, a thunderstorm can be 40,000 times more
powerful than a tornado. Then why aren't thunderstorms as dangerous as
tornadoes? The answer lies in each storm's
energy
density.
A tornado may not have nearly as much energy as a thunderstorm, but the
energy in the tornado is concentrated into a much smaller area. Imagine
you have a hose and are watering a yard. You can spray five gallons of
water over the whole yard and not really notice it. If you were to spray
a couple gallons in one small section, you would probably flood and
possibly start to erode it. That's because the water was very
concentrated, like the energy in a tornado.
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