Gregor Cuzak

on marketing, business and philosophy

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Sparks fly

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Electricity jumps through air at 30 kV/m (thirty thousand volts per meter). This means that it can jump a meter away if the voltage is 30.000 V. Or 1 centimeter if it is 300 V, like from your car to your finger after the drive, ouch. Or 100 meters if the voltage is 3 MV, like from a cloud to a treetop, baaammmm.

Did you know that the electric field of the Earth is 100 V/m? It simply means that anything lifted by two meters is essentially at almost 220 V, which sounds crazy. The reason why we don’t get killed by it is because the voltage equalizes through contact. Anything touching the ground is at the same voltage. However, once lifted or isolated, like a car on tyres, the voltage differential builds up.

Another bizzare consequence of this electric field is the possibility for levitation. If you want to lift something in midair and keep it there, just pump it up with a very small amount of positive electric charge. Eventually you could also achieve it if you were able to control a very small part of particles in the object you would want to lift. Say that your object has one k-mole of atoms, which is roughly 6 * 10^26 atoms. If they are Carbon atoms, this lump should weigh around 12 kg. To lift this lump up, you would need to counterbalace the gravity, here this would be 120 Newton, roughly. You get 120 N of electric force if you fill a condensator with 7 * 10^18 electrons. This seems a lot, but it is not. It is only one electron in ever 100 million carbon atoms, and the carbon atoms have 6 electrons each. So more or less levitation is about attaining control over roughly one billionth of matter.

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