How to make flame levitate
Make the flame levitate!
Warning! Only under adult supervision
- ballpoint pen;
Remove the ink cartridge from a pen and pull out its tip. Cover a lighter’s nozzle with ink and click the lighter – the flame levitates!
Ink has high viscosity, so if you use it to cover a nozzle that is releasing gas, it decreases the nozzle’s diameter, which increases the velocity of the gas flow and decreases the occurrence of inhomogeneities in the flow. This prevents the combustible gas from mixing with oxygen from the surrounding air at the base of the jet, and, as you know, there can be no fire without oxygen. Therefore the inhomogeneities, and thus the flame, form in the upper section of the gas jet, which is slowed by the viscosity of the air!
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