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russ_watters said:Yes!
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No, it is no more complicated than that - you have it exactly right. Have you ever noticed condensation or frost on the outside of your car windows in the morning...but not necessarily on the hood or sides of the car? Ever wonder why...? Now you know!ideogram said:lol so this is related to black-body radiation? Does this actually translate to real-world examples, say I have a car with black upholstery that gets hot fast during the day, will it cool down faster at night than a car with white upholstery? Or is it more complicated than that?
Academic said:I still don't understand how the color of an object affects its cooling at night. The power it puts off as a black body is proportional to its temperature, not its color. Is it simply because it gets hotter during the day that it cools down faster at night?
confused about this
Yes, however an object can only cool below ambient via radiation.hamster143 said:I think there are two distinct mechanisms here.
Black body will lose more energy on radiation towards the sky at night, at the same temperature. But radiation may not be the primary cooling mechanism, especially for large and relatively cool objects. The cooling rate of an object with characteristic dimension ~1 m at room-temperature due to black-body radiation is on the order of 1 degree per hour. It will probably cool faster because of heat exchange with the atmosphere.
Further clarification: "black" doesn't just mean the color we can see, but also has to be applied to infrared to adequately deal with radiation. An object that is black in visible light color may or may not be "black" in the infrared.hamster143 said:Power is proportional to emissivity times temperature to the fourth power. Emissivity is higher for dark-colored objects, lower for bright colored and reflective objects...
Since light-colored objects absorb less than 100% of incident radiation, it follows that they must also emit less.
Black objects have a higher ability to absorb light and heat compared to other colors. This means that during the day, when there is more sunlight, the black object will absorb more heat and warm up faster.
Yes, the material of the black object can affect its warming and cooling. Materials with a higher thermal conductivity will allow heat to transfer more quickly, resulting in a faster warming and cooling process.
Yes, this statement is generally true. Black objects have a higher ability to release heat compared to other colors, so they will also cool down faster at night when there is less sunlight and heat available to absorb.
The color of an object affects its temperature because different colors have different abilities to absorb and release heat. Darker colors, such as black, have a higher ability to absorb heat and therefore, will have a higher temperature compared to lighter colors.
Not necessarily. While it is generally true that black objects will warm up and cool down faster, other factors such as the material and environment can also affect the speed of the warming and cooling process. Additionally, the specific shade of black can also make a difference in how quickly the object warms and cools.