151. The thermal efficiency of petrol and gas engines is about September 13, 2025 by Admin 15% 30% 50% 70% ✅ The correct answer is option B.
152. Alpha-methyl-naphthalene (C11 H10) has a cetane number of September 13, 2025 by Admin 0 50 100 120 ✅ The correct answer is option A.
153. The air-fuel ratio of the petrol engine is controlled by September 13, 2025 by Admin carburettor injector governor none of these ✅ The correct answer is option A.
154. The thermodynamic cycle on which the petrol engine works, is September 13, 2025 by Admin Otto cycle Joule cycle Rankine cycle Stirling cycle ✅ The correct answer is option A.
155. A turbo-jet does not require a turbine to drive the compressor. September 13, 2025 by Admin TRUE FALSE ✅ The correct answer is option B.
156. A diesel engine has inlet valve, fuel injection valve and exhaust valve. September 13, 2025 by Admin Yes No ✅ The correct answer is option A.
157. In a petrol engine, if diesel is used, then the engine will September 13, 2025 by Admin not run run more efficiently run at high speed explode ✅ The correct answer is option A.
158. Materials which make good moderators do not make good reflectors. September 13, 2025 by Admin Correct Incorrect ✅ The correct answer is option B.
159. The delay period in compression ignition engines depends upon September 13, 2025 by Admin temperature and pressure in the cylinder at the time of injection nature of the fuel mixture strength relative velocity between the fuel injection and air turbulence pressure of residual gases all of the above ✅ The correct answer is option D.
160. A diesel engine has compression ratio from September 13, 2025 by Admin 6 to 10 10 to 15 15 to 25 25 to 40 ✅ The correct answer is option C.