Bodies Prepared With Separately Uniform Temperatures, Then Put Into Purely Thermal Communication Wit
If bodies are prepared with separately uniform temperatures, and are then put into purely thermal communication with each other, by conductive or radiative pathways, they will be in thermal equilibrium with each other just when they have the same temperature, and then there will be no net transfer of heat between them; but if initially they do not have the same temperature, heat will flow from the hotter to the colder, by whatever pathway, conductive or radiative, is available, and this flow will continue until thermal equilibrium is reached and then they will have the same temperature.
One form of thermal equilibrium is radiative exchange equilibrium. Two bodies, each with its own uniform temperature, in solely radiative connection, no matter how far apart, or what partially obstructive, reflective, or refractive, obstacles lie in their path of radiative exchange, not moving relative to one another, will exchange thermal radiation, in net the hotter transferring energy to the cooler, and will exchange equal and opposite amounts just when they are at the same temperature. In this situation, Kirchhoff's law of equality of radiative emissivity and absorptivity and the Helmholtz reciprocity principle are in play.
Read more about this topic: Thermal Equilibrium
Famous quotes containing the words put, purely, bodies, uniform, separately, prepared and/or wit:
“Have you never been moved by poor men’s fidelity, the image of you they form in their simple minds? Why should you always talk of their envy, without understanding that what they ask of you is not so much your worldly goods, as something very hard to define, which they themselves can put no name to; yet at times it consoles their loneliness; a dream of splendor, of magnificence, a tawdry dream, a poor man’s dream—and yet God blesses it!”
—Georges Bernanos (1888–1948)
“The motion picture made in Hollywood, if it is to create art at all, must do so within such strangling limitations of subject and treatment that it is a blind wonder it ever achieves any distinction beyond the purely mechanical slickness of a glass and chromium bathroom.”
—Raymond Chandler (1888–1959)
“Southern trees bear a strange fruit
Blood on the leaf and blood at the root
Black bodies swingin’ in the southern breeze
Strange fruit hangin’ in the poplar trees.”
—Billie Holiday [Eleanor Fagan] (1915–1959)
“We call ourselves a free nation, and yet we let ourselves be told what cabs we can and can’t take by a man at a hotel door, simply because he has a drum major’s uniform on.”
—Robert Benchley (1889–1945)
“What if there are not only two nostrils, two eyes, two lobes, and so forth, but two psyches as well, and they are separately equipped? They go through life like Siamese twins inside one person.... They can be just a little different, like identical twins, or they can be vastly different, like good and evil.”
—Norman Mailer (b. 1923)
“Dad, if you really want to know what happened in school, then you’ve got to know exactly who’s in the class, who rides the bus, what project they’re working on in science, and how your child felt that morning.... Without these facts at your fingertips, all you can really think to say is “So how was school today?” And you’ve got to be prepared for the inevitable answer—”Fine.” Which will probably leave you wishing that you’d never asked.”
—Ron Taffel (20th century)
“I love every-day senses, every-day wit and entertainment; a man who is only good on holidays, is good for very little.”
—Philip Dormer Stanhope, 4th Earl Chesterfield (1694–1773)