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 Where Your Dreams Become Reality |
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You are reporting the following post to the moderators for review and possible removal from the forum Poster: heat transfer engineer Subject: RE: why no caps on hot days? Body: the point of a "breathable" light colored hat is that it does not prevent air from flowing over the head (or through the hair, i suppose) so it does not limit the convective cooling and evaporative cooling from the head. however, since it is white, it theoretically reflects more thermal radiation from the sun than a full head of dark hair would. darker colors tend to absorb radiation, and thermal radiation is not exception. "most" of the heat lost from the body in cold climates is from the head and hands because those are generally the only exposed parts of the body (youre usually not out in a snowstorm without shoes and socks or something covering the netherlands). also, the body will make the biggest effort to keep the head (and head skin) at a high enough temperature as opposed to the skin and tissue in the feet, legs, arms, hands, etc, which the body will happily let go "cold". as a result, the head stays the hottest when it is cold, causing it to loose the most heat, because heat loss is roughly proportional to the bulk temperature differential between the surface and the fluid (air) flowing around it. Hit the submit button below if you want us to review the post. If you feel this is urgent or want a reply, email us at letsrun@letsrun.com about the post and please include a link to the thread the post is on and what page number/post on that page it is
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