218. The compression ratio for Diesel engines is
A.3 to 6
B.5 to 8
C.15 to 20
D.20 to 30

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219. In an isothermal process,
A.There is no change in temperature
B.There is no change in enthalpy
C.There is no change in internal energy
D.All of these

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220. The heating and expanding of a gas is called thermodynamic system
A.Yes
B.No
C.
D.

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221. Otto cycle efficiency is higher than Diesel cycle efficiency for the same compression ratio and heat input because in Otto cycle
A.combustion is at constant volume
B.Expansion and compression are isentropic
C.Maximum temperature is higher
D.Heat rejection is lower

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222. Fuels have higher calorific value than solid fuels.
A.Yes
B.No
C.
D.

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223. The free expansion process is __________ non-flow process.
A.Reversible
B.Irreversible
C.
D.

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224. The gas constant (R) is equal to the __________ of two specific heats.
A.Sum
B.Difference
C.Product
D.Ratio

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