The thermal efficiency of a diesel cycle having fixed compression ratio with increase in cut-off ratio will a. increase b. decrease c. independent d. increase or decrease depending upon other factors

The thermal efficiency of a diesel cycle having fixed compression ratio with increase in cut-off ratio will  a. increase  b. decrease  c. independent  d. increase or decrease depending upon other factors  
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A diesel engine is usually more efficient than a spark ignition engine because a. Diesel being a heavier hydrocarbon, release more heat per kg than gasoline b. The air standard efficiency of diesel cycle is higher than the Otto cycle, at a fixed compression ratio c. The compression ratio of a diesel engine is higher than that of an Spark ignition engine d.Self ignition temperature of diesel is higher than that of gasoline.

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An ideal air standard Otto cycle has a compression ratio of 8.5. If the ratio of the specific heats is 1.4, then what is thermal efficiency (in percentage) of the Otto cycle? a. 57.5% b. 45.7% c. 52.5% d. 95%

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Last Answer : ANSWER b. decrease

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The coefficient of performance is the ratio of the refrigerant effect to the (a) heat of compression (b) work done by compressor (c) enthalpy increase in compressor (d) all of the above

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Last Answer : Ans: d

If petrol is used in a diesel engine a. higher knocking will occur b. efficiency will be low c. low power will be obtained d. black smoke will be produced

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