"A very simple experiment shows that a black surface is a better radiator, or pours out more energy when hot, than a surface which does not absorb fully, but reflects much of the radiation which falls upon it. If a platinum foil with some black marks on it be heated to redness, the marks, black when cold, are much brighter than the surrounding metal when hot; they are, in fact, pouring out much more visible radiation than the metal."
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University of Cambridge alumniFellows of the Royal SocietyAcademics from the United KingdomPhysicists from EnglandPeople from Manchester
Original Language: English
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John Henry Poynting
John Henry Poynting FRS (9 September 1852 – 30 March 1914) was an English physicist, known for the Poynting vector and Poynting's theorem.
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