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About:
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Refrigerator Mould
A Refrigerator Mould is an open system that dispels heat from a closed space to a warmer area, usually a kitchen or another room. By dispelling the heat from this area, it decreases in temperature, allowing food and other items to remain at a cool temperature. Refrigerators appear to violate the Second Law of Thermodynamics, but the key reason they do not is because of the work needed as input to the system. They are essentially heat pumps but work to cool a region instead of heat it.
A refrigerator causes heat to flow from cold to hot by inputting work, which cools the space inside the refrigerator. ;
Work is inputted which compresses a coolant, increasing its temperature above the room's temperature.
Heat flows from this coolant to the air in the room, reducing the temperature of the coolant.
The coolant expands, and it cools down below the temperature inside the refrigerator.
Heat flows from the refrigerator to the coolant, decreasing the temperature inside.
This process is cyclical and allows refrigerators to be run for as long as necessary. The work needed as input to the system is given by the equation
Vacuum Cleaner Mould
A vacuum cleaner mould, also known simply as a vacuum or a hoover, is a device that causes suction in order to remove dirt from floors, upholstery, draperies, and other surfaces. It is generally electrically driven.
The dirt is collected by either a dustbag or a cyclone for later disposal. Vacuum cleaners, which are used in homes as well as in industry, exist in a variety of sizes and models—small battery-powered hand-held devices, wheeled canister models for home use, domestic central vacuum cleaners, huge stationary industrial appliances that can handle several hundred liters of dust before being emptied, and self-propelled vacuum trucks for recovery of large spills or removal of contaminated soil. Specialized shop vacuums can be used to suck up both dust and liquids.
Vacuum cleaners’ simple yet effective design has done away with having to clean dust and other small particles off surfaces by hand, and turned house cleaning into a more efficient and fairly rapid job. Using nothing but suction, the vacuum whisks away dirt and stores it for disposal.
The power of a vacuum cleaner is determined not just by the power of its motor, but also the size of the intake port, the part that sucks up the dirt. The smaller the size of the intake, the more suction power is generated, as squeezing the same amount of air through a narrower passage means that the air must move faster. This is the reason that vacuum cleaner attachments with narrow, small entry ports seem to have a much higher suction than a larger one.
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