For cooling purposes, the mixed air temperature of an air handling unit is set to maintain what temperature?
a) 5ºC
b) 7.5ºC
c) 10.5ºC
d) 12.5ºC
e) 15ºC
Answer: D
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Power Engineering
- The work done in a constant pressure expansion can be determined by:
- If 10.4 m³ of air is compressed at a constant temperature to 5.1 m³ and 750 kPa gauge. Calculate how much work is done on the gas, assuming atmospheric pressure to be 100 kPa.
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- Find the characteristic constant for a gas if 112 kg of the gas has a volume of 5.7 m³ at 1500 kPa absolute and 27.5°C.
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- If 0.25 m³ of a gas at 4000 kPa gauge pressure is expanded until the gauge pressure is 500 kPa and the expansion is polytropic with n = 1.35. Find the final volume the gas will occupy. Note: Assume atmospheric pressure = 100 kPa
- The equation (PV/T) = mR or PV = mRT is called the:
- The Characteristic Constant of each perfect gas is
- The pressure-volume diagram of a typical air compressor will have a curve drawn:
- If 10.4 m³ of air is compressed at a constant temperature to 5.1 m³ and 750 kPa gauge. Calculate how much work is done on the gas, assuming atmospheric pressure to be 100 kPa.
- Compression and expansion in real life cases will always follow the polytropic process that is described by the formula(s):
- The formula Work = (P1V1 - P2V2) / n - 1 is used to describe expansion during:
- To "expand a gas" means the gas is:
- The work done in a constant pressure expansion can be determined by:
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- The General Gas Law can be written using the formula/s:
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- Absolute pressure can be defined as:
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