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Emissivity of the black body is 1. And this is probably the reason that the condenser of refrigerator is painted black to loose heat efficiently by radiation ,though there are other modes of heat transfer like conduction and convection which is not affected by colour of the body
What else can I help you with?
What is the correct CSS for adding a background image to a page?
Use the attribute BGCOLOR=".." inside the start Body tag using the color you want as the value. It should look like this: this will give you a black background, and at the end of your HTML document you close the Body Of cause if you use a black background you cannot use black font. You won't be able to see it. You can set the value=".." of the background to what ever you like.
Who was the first Black person to invent Technology?
No single person black, white, yellow or green invents technology. Technology is a body of knowledge added to by individuals and groups. Sometime it is known who added a part of that knowledge and when they did so. At other times is is not known, especially very early additions.
What attibute you use in the body tag to give the background a solid color?
You use the style attribute to add any presentation to your BODY element, including background-color. This is the code to make an HTML document with a red background. <body style="background-color: red"> You can also add a stylesheet to the head of the document (or an external file, if you're going to have the same rules on more than 1 page.) <style type="text/css"> body { background-color: #f00; } /* Short of ff0000 which is hex for "red" */ </style>
Was John lee love black?
yes, john lee love was black his father was white and mother was black so yes he was black
What difference is there between black patent and black PU colour?
black patent is the really shiny one, whereas the black pu is the dull, unshiny looking one
What is the significance of black body emissivity in the context of thermal radiation?
Black body emissivity is a measure of how efficiently an object emits thermal radiation. In the context of thermal radiation, black body emissivity is significant because it determines how much heat an object can radiate and absorb. Objects with high emissivity can efficiently emit and absorb thermal radiation, while objects with low emissivity are less effective at exchanging heat with their surroundings. This property is important in various applications, such as in designing thermal systems and understanding the behavior of materials at different temperatures.
What is the definition of 'emissivity'?
The term "emissivity" refers to the relative power of a surface to emit heat by radiation. It could also be defined as the ratio of energy radiated by a particular material to energy radiated by a black body.
What is the emissivity of human skin and how does it affect the body's ability to regulate temperature?
The emissivity of human skin is around 0.98, which means it is very good at emitting heat. This high emissivity helps the body regulate temperature by allowing excess heat to be released into the environment, helping to cool the body down.
What is the emissivity of black anodized aluminum and how does it affect its thermal properties?
The emissivity of black anodized aluminum is typically around 0.85 to 0.95. A higher emissivity means that the material can more effectively emit thermal radiation, which can impact its thermal properties by allowing it to cool down faster and more efficiently. This can be beneficial for applications where heat dissipation is important.
Do reflector panels have high or low emissivity?
low emissivity
What are factors on which the amount of heat radiated by a body depends?
The amount of heat radiated by a body depends on factors such as its temperature, surface area, and emissivity. Higher temperatures, larger surface areas, and higher emissivity values generally result in greater heat radiation.
A material with zero emissivity radiates to other body in vacuum or not?
Zero emissivity means generally no radiation for the far-field. However, for the near-field case, energy may flow to another bodies.
How does a silver surface work in radiation?
The concept involved here is Emissivity - the ability to emit energy. e is the usual symbol, and a perfect emitter would have an e of 1. Your perfect black body will have this emissivity of 1.A highly polished surface (polished at all the wavelengths concerned) will have an emissivity much smaller. Polished silver has an emissivity of about 0.02.In general the emissivity of a surface is inversely related to its reflectance, but this does vary with the surface finish, colour, and the mass of the object.It is worth noting, that low emissivity glass is used with effect in the double glazing of windows.
What is the emissivity of an ideal reflector?
The emissivity of an ideal reflector is 0, meaning it reflects all incoming radiation without emitting any.
What is the emissivity of silicon?
The emissivity of silicon can vary depending on the specific type of silicon (e.g., monocrystalline, polycrystalline) and surface condition. However, typically, the emissivity of silicon is around 0.65-0.75 in the infrared spectrum.
Why is Ice a black body?
It's not. The term "black body" is used to describe a hypothetical perfectly black object that reflects no light at all .here the light refers to entire electromagnetic spectrum. Although the emissivity of ice is near about 0.95 hence it behaves more as black body (emmisivity = 1) than a white body. The reason is for ice to be near about black body is that ice is a very good absorber of radiation outside the visible region (eg for infrared rays ) . Hence ice is more a black body than a white body (as in appearance ).
Why heat sinks are black anodized?
Radiative heat transfer (heat transfer by electromagnetic radiation) is proportional to e*(T1^4 - T2^4) where T1 is the absolute temperature of the material, T2 is the absolute temperature of the surroundings, and e is the emissivity coefficient. A black material has a high emissivity coefficient, while a silvery material has a low emissivity coefficient. However, the emissivity coefficient cuts both ways, so to speak. A black material in thermodynamic equilibrium with its environment absorbs more radiation, true. But it also emits more radiation (this is necessary for equilibrium to hold). Likewise, a silvery material absorbs less radiation, and also emits less radiation. Conductive heat transfer ensures that the black material on the surface of the heat sink remains hot. The surroundings are at a lower temperature. Therefore T1 and T2 are set, and the heat transferred from the heat sink to the surroundings is simply proportional to e, the emissivity coefficient.
