Here's what I found on a website "Depending on which website you believe it is anywhere between 20% and 90%.
However it appears that the big difference is accounted for by the prevailing circumstances.
Conduction and convection about 25%
Radiation about 43%
Evaporation and moisture about 30%
Exhaled air about 2%
Evaporation prevails at high ambient temperatures. Conduction and convection prevail at low ambient temperatures."
The generally accepted overall amount of heat loss through an uncovered head is about 40%, which is substantial. Wearing a hat can make a big difference in how cold you get overall, and how fast you get cold.
I gotta go with the NY Times on this one. It would seem that it's not entirely true. Body heat escapes through any exposed surface. The larger the surface, the more heat that escapes. If you have less hair, naturally, you'll lose more heat through your head (I happen to shave mine, so I know!) http://www.nytimes.com/2004/10/26/health/26real.html
There are many factors that affect the loss of energy:1 the resistance of the wire2 the kettle will keep most heat in but not all heat within the kettle so more energy is lost3 the water will evaporate out the top and that is also a cause. (they can't close it off otherwise the pressure would build and it would explode).
Square feet has nothing to do with how much an X BTU heater can heat, heat is calculated by determining how much heat LOSS there is to make up for. AC is the exact opposite, it's size is determined by how much heat GAIN there is. In general, a 120,000 BTU boiler can heat an average well insulated 2 story house, no problem. There are many programs that calculate heat loss/gain but since there are people who do it for a living, try asking one.
btus needed to heat & cool 625sf room
how many square feet does a 14,000 btu heater heat
i think because most body heat escapes from your head.
You wear a hat in the winter to keep your head warm. It is not true that your body heat escapes from your head.
I gotta go with the NY Times on this one. It would seem that it's not entirely true. Body heat escapes through any exposed surface. The larger the surface, the more heat that escapes. If you have less hair, naturally, you'll lose more heat through your head (I happen to shave mine, so I know!) http://www.nytimes.com/2004/10/26/health/26real.html
Earmuffs work by keeping the heat from your ears near your ears, instead of letting it escape into the air. Most of your body heat escapes from your head and feet. Covering your ears helps to warm your entire body.
A hat keeps you warm not only because it is additional clothing, but also because most of you body heat escapes from your head, therefore by wearing a hat, you trap more body heat in.
Body heat escapes from all of your body. It escapes more in places where we sweat more often, such as the armpits and forehead. It escapes when we blush as the blood is closer to the surface of the skin so heat can escape easier.
No. It does not heat up the body. On the contrary it keep your head cool by reflecting the light. Lol.
Most of the heat in the body is produced as a byproduct of metabolic processes, especially in organs like the liver, brain, and heart. Additionally, muscle activity such as shivering or exercising can generate heat.
Human head hair tends to be longer, finer, and more pigmented than body hair. It also grows at a faster rate and has a longer growth phase compared to body hair. Additionally, head hair is more responsive to hormones and environmental factors, resulting in differences in texture and appearance compared to body hair.
The rate at which heat escapes from a body depends on factors such as the body's surface area, temperature difference between the body and its surroundings, and the body's thermal conductivity. In general, heat loss can occur through conduction, convection, and radiation. Warmer bodies will lose heat faster than colder bodies.
heat escapes from 2 major places, your head and your feet, the padding on your feet trap the heat in your feet, while the hair are your head traps the heat from escaping there
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