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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.
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A technician has a room of computers which are running very hot The technician discovers that the heat sinks in the computers are very dusty What should the technician use to clean the heat sinks?
The technician can use an anti static vacuum. or you can use some type of compressed air.
Where on a computer would you most likely find a heat spreader?
A heat SPREADER is typically on the RAM, and has never been factually proven to be effective without being combined with a heat SINK. As for heat SINKS... Typically CPU, Videocard, and Northbridge. But it may also appear on the South Bridge, RAM, Harddrives, I/O controllers, MOSFETs, Coprocessors, and Network Devices.
What does a heat sink do?
A heat sink is usually something that draws something away from an electrical componet (Ex: ICU's, Processors and transistors) APEX- A device that absorbs and draws heat from a hot object, dispersing it into the surroundings.
What is the specific heat of sinter?
Specific heat of sinter
What is the difference between flame and heat?
"Flame" is the visible energy when burning something. "Heat" is given off a flame and countless other things. Flame produces heat, but heat does not always generate from flame, and heat almost never produces flame (friction might count). And if you want the definitions: HEAT: a form of energy that is transferred by a difference in temperature. FLAME: the process of combustion of materials producing heat and light and (often) smoke. If you want to think of it a different way: Flame is what you see when you look at a fire and heat if what you feel from the fire.
What is used for heat dissipation in ICs?
heat sinks
Does cold rise and heat sink?
No, cold sinks and heat rises.
What are the functions of the heat?
The main purpose of a heat sink is to expel heat from a generating source. Heat sinks work through the process of conductive and convection heat transfer. Heat sinks are a passive form of cooling, as they have no moving parts and require no power.
Why can aluminum be anodized?
aluminum is anodized due to its unique features.
Is there any way to get my cookware anodized?
No, you have to purchase cookware that is already anodized. It is well worth it! Anodized cookware lasts forever!
Are Some heat sinks packaged as part of a processor chip?
Some heat sinks are packaged as part of a processor chip. This is done to reduce costs and potential user error.
When air loses its heat becomes less dense and sinks?
no
Are small components typically made out of aluminum with fins that help to dissipate heat?
heat sinks
What causes us to think that heat rises?
Because of convection: heat rises and cold sinks
Why does anodized alumium not react with acidic foods?
Because the anodized layer protects it.
What is compact heat sinks?
Heat sinks are devices that sap heat from components inside your computer, a compact heat sink would be the same device in a smaller fashion, designed to go in small form factor pc's the inherently don't have a lot of space.
What should the technician use to clean the heat sinks?
The cleaning of heat pipes and sinks can be done with two different chemicals (among others). Highly purified Isopropyl alcohol and chemist grade acetone are two examples. That being said if the heat sinks and pipes are made of copper do not expose them to ammonia which can react.
