oczywiscie, jest to prawda:To jest czysta fizyka i jest to mozliwe dla kazdego. Co mam pelne prawo napisac, bo sam przez te wegle przeszedlem i wiem co mowie.
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lub dla leniwych:
Explanation
When two bodies of different temperatures meet, the hotter body will cool off, and the cooler body will heat up, until they are separated or until they meet at a temperature in between.[3] What that temperature is, and how quickly it is reached, depends on the thermodynamic properties of the two bodies. The important properties are temperature, mass, specific heat capacity, and thermal conductivity.
The product of mass and specific heat capacity is called heat capacity and tells how much heat energy the body needs to heat it up by one degree. Since the heat taken in by the cooler body must be the same as the heat given by the hotter one, the end temperature will lie closer to the temperature of the body with the greater heat capacity. The bodies in question here are human feet, which mainly consist of water, and burning coals.
David Willey, professor of physics, explains that there is nothing supernatural about firewalking.[4] Willey notes that most fire-walks occur on coals that measure about 1,000 degrees Fahrenheit (538 degrees Celsius), but he once recorded someone walking on 1,800-degree (982 °C) coals.[1]
Factors that prevent burning
Factors that act together to prevent the foot from burning
Water has a very high heat specific capacity (4.18 kJ/K kg), whereas coals have a very low one. Therefore the foot's temperature will change considerably less than the coal's.
Water also has a high thermal conductivity, and on top of that, the blood in the foot will carry away the heat and spread it. On the other hand, coal has a poor thermal conductivity, so the hotter body consists only of the parts of the coal which is close to the foot.
When the coal cools down, its temperature sinks below the flash point, so it stops burning, and no new heat is generated.
The coals are often covered with ash, which is a poor heat conductor.
The coals are a very uneven surface, and the actual surface area of foot touching the coals is very small.
Firewalkers do not spend very much time on the coals, and they keep moving.
Risks when doing firewalking improperly
There are risks when doing firewalking improperly
People have burned their feet when they remained in the fire for too long, enabling the thermal conductivity of the coals to catch up.
Foreign objects in the coals may result in burns. Metal is especially dangerous since it has a high thermal conductivity.
Coals which have not burned long enough can burn feet more quickly. Coals contain water, which increases their heat capacity as well as their thermal conductivity. The water must be evaporated already when the firewalk starts.
Wet feet can cause coals to cling to them, increasing the exposure time.
Therefore, while firewalking is explained with simple physics, there are still hazards. Notably in 2002, 20 managers of the KFC fast food chain in Australia received treatment for burns caused by firewalking.[5]
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) że nie jest to związane ze zwykłą fizyką i , czego nie ukrywam i można powiedzieć doceniam ( na swój sposób :wink: ) cyrkowych umiejętności starszego pana, czy ekipy mnichów z klasztoru Shaolin, co robią demolkę cegłom i sie na włócznie nabijają z dużym entuzjazmem.
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