A video of a man who seemingly passed his hand through a stream of molten metal without burning himself became viral this past month. While some may think it’s the work of video editing, it's actually quite simple.
You may have already seen the viral video of the man who passes his hand through a flowing stream of molten steel, like a cat playing with a faucet. When we first saw it, we thought there was no way this guy was actually doing this; surely he’d burn his hand to a crisp if it was real. However, the video is one hundred percent authentic and can be explained by science!
Before getting into the explanation, we’ve got to say that regardless of whether or not this man was able to do it does not mean you should attempt this at home under any circumstance. The melting point of aluminium is 660 degrees Celsius and the metal found in the video is surely above 1,000 Celsius given its glowing white colour. Even if the science says you may be safe, if anything goes wrong then it could spell the end for you.
The Leidenfrost Effect
The phenomenon behind the feat displayed in the video is called the Leidenfrost Effect. It’s likely you may have already seen this first hand on the hob in the kitchen. When subjected to certain high temperatures, water will begin to form drops that bounce and move freely.
When these water drops come in contact with a surface exceeding a certain temperature – typically accepted to be around 193 Celsius – its bottom evaporates. The result is a small gas cushion that forms underneath the drop; it allows it to travel freely seemingly by levitation. This air cushion actually acts as a barrier between the hot surface and the drop, briefly protecting it and allowing it to move around before evaporating.
The key in this video is the moisture found upon the man’s hand as well as the amount of time his hand spends in the stream. The water on his hands is instantly heated to a temperature exceeding the threshold to allow the effect to occur, giving him this gas barrier. However, should his hand spend a bit more time in the molten metal, it would be curtains for him.
Science is pretty cool, right?