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Equilibrium Temperature Question?

Equilibrium Temperature Question?

Answer:

Objects in outer space that do not have their own heat source will heat up or cool off until their temperature is such that they emit exactly as much thermal energy as they receive from the SunThis temperature is called the equilibrium temperatureA planet that is d times further away from the Sun than the Earth and that is pitch-black so that it absorbs all the sunlight that falls on it will have an equilibrium temperature that is equal to Teq 279/SQRT(d) kelvin or Teq 279/SQRT(d) - 273 degrees C, or Teq 502/SQRT(d) - 460 degrees F where SQRT is the square-root functionIf the planet is not pitch-black but actually reflects part of the sunlight, then its equilibrium temperature will be lower because it does not get heated up quite so muchIf the planet has an atmosphere, then its surface temperature may be much higher than the equilibrium temperature because an atmosphere works like a blanket If a pitch-black planet without an atmosphere always shows the same side to the Sun and if the heat does not travel, then the point at which the Sun is straight overhead gets a temperature of Thot 394/SQRT(d) kelvin, or Thot 394/SQRT(d) - 273 degrees C, or Thot 710/SQRT(d) - 460 degrees F Teq is an upper estimate for the average temperature on the outside of the atmosphere (if any) of planets that rotate fast or that have a thick atmosphere that rotates fast, which means all planets except MercuryThot is an upper estimate for the hottest temperatures on planets without atmospheres that rotate slowly, such as Mercury, and also for the MoonThere is no lower limit on how cold the dark side of a planet or Moon can get; this mostly depends on how fast the planet rotatesSlow rotators cool off more than fast rotators.
Divide the number of atoms given by Avogadro's Number (6.022 x 10^23 mol^-1)This will give you the answer you seek.

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