Mechanical Engineering - Heat Transfer, Refrigeration and Air Conditioning
Exercise :: Heat Transfer, Refrigeration and Air Conditioning - Section 5
36. |
The mass of water vapour present in 1 kg of dry air, is called humidity ratio. |
Answer: Option A
Explanation:
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37. |
In a vapour compression refrigeration system, a throttle valve is used in place of an expander because |
A. |
it considerably reduces mass of the system | B. |
it improves the C.O.P., as the condenser is small | C. |
the positive work in isentropic expansion of liquid is very small | D. |
it leads to significant cost reduction |
Answer: Option C
Explanation:
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38. |
The unit of overall coefficient of heat transfer is |
Answer: Option A
Explanation:
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39. |
Most thermostatic expansion valves are set for a superheat of |
Answer: Option A
Explanation:
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40. |
For large tonnage (more than 200 TR) air-conditioning applications, the compressor recommended is |
A. |
reciprocating | B. |
rotating | C. |
centrifugal | D. |
screw |
Answer: Option C
Explanation:
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