Q2.For the same compression ratio the thermodynamic cycles in the order of decreasing efficiencies are

(A) Dual, Diesel, Otto

(B) Dual, Otto, Diesel

(D) Otto, Dual, Diesel

Ans: (C) Diesel, Dual, Otto

*for same compression ratio Otto cycle work on high efficiency as compare to diesel cycle.. because diesel cycle work on compressed air fuel mixture ignition that don't have spark plug due to this clearance volume of diesel cycle is less and compression ratio is high as compare to Otto cycle.

*compression ratio:

=Total volume of cylinder/clearance volume of cylinder

=V/Vc

Compression ratio look like 14:1 that means

Total volume of cylinder =14

Clearance volume of cylinder =1

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