How can people walk on burning coal and not burn themselves?
Asked by: Jeff


Before a person walks through burning coal, the person will make sure their feet are very wet. When they start walking on the coal, this moisture will evaporate and form a protective gas layer underneath the person's feet.

You can see examples of this if you happen to drip some water on a hot stove or any very hot surface. The water will very easily glide around on top of a newly formed layer of air underneath it -- like air hockey pucks on an air hockey table.

Note that when someone walks through burning coal, typically this is also done very quickly to prevent a great deal of exposure to possible harm. By walking quickly, thinking positively, and letting the water cushion you from immediate danger over a short distance, such a task is possible.

You may have also heard of physics teachers demonstrating how this principle works by sticking their hand first in a bucket of water and then quickly in a bucket of boiling molten lead. In the lead, their hand is protected briefly by a layer of gas from the evaporated water (the water vapor).

I'm fairly sure that there is a name for this particular layer of gas, but I'm afraid the name is beyond me at the moment.

In other words, water vapor has a low heat capacity and poor thermal conduction. Very often, the coals or wood embers that are used in fire walking also have a low heat capacity. Sweat produced on the bottom of people's feet also helps form a protective water vapor. All of this together makes it possible, if moving quickly enough, to walk across hot coals without getting burned.

WARNING: Do not attempt to perform any of the actions described above. You can seriously injure yourself.
Answered by: Ted Pavlic, Electrical Engineering Undergrad Student, Ohio St.

Support Us

Help us keep going. Donate now. Thank you for your support!

Science Quote

'In a way science is a key to the gates of heaven, and the same key opens the gates of hell, and we do not have any instructions as to which is which gate. Shall we throw away the key and never have a way to enter the gates of heaven? Or shall we struggle with the problem of which is the best way to use the key?'

Richard Phillips Feynman

All rights reserved. © Copyright '1995-'2015