Simply Science once again answers your questions this week recorded at our kiosk at the Science Museum of Minnesota. You too, can ask us a question and we may answer it on-air!
Question: "Sven, why are some raindrops larger than others, how come they have different sizes?"
Answer: Raindrops of course do have different sizes ranging from drizzle to large rain drops in tropical or thunderstorm systems. It depends really on time, because rain drops from by bumping into other rain drops. The longer that cloud is sustaining rain above the ground, so thunderstorms the rain drops stay above ground longer, so they can grow bigger. When we call a rain drop a rain drop it has to be officially be 0.02" in size in diameter or larger. Speed depends on size. Drizzle may only move 4 mph toward the ground but larger rain drops can move 20 to 25 mph.
Question: "When lightning strikes the ground, why does it burn?"
Answer: Well, any reaction in the atmosphere or anywhere on the planet with lots of energy is usually very hot, a result of that energy. Lightning of course is very strong because we have lots of electricity, so it can be 30 to 50 thousand degrees, four to six times hotter than the surface of the sun!
Question: "Why do tornadoes spin different directions?"
Answer: Well, we have to talk a little bit about coriolis force (the force caused by earth's rotation), that's the force that causes winds to move in different directions depending on if you're in the northern or southern hemisphere. Tornadoes typically rotate counter-clockwise like most air that is rising upward, but it's not because of earth's rotation because we're looking at a very small scale dynamic, when we're looking at tornadoes, but the winds that allow storms to develop in the northern hemisphere are influenced by the earth's rotation so our tornadoes do normally spin counter-clockwise.
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