31. The advancing of spark timing in spark ignition engines will __________ knocking tendency.
A. increase
B. reduce
C. not effect
32. The knocking in spark ignition engines can be reduced by
A. retarding the spark
B. increasing the engine speed
C. both (a) and (b)
D. none of these
33. An atom bomb utilizes uncontrolled nuclear fission.
A. True
B. False
34. The ratio of the brake power to the indicated power is called
A. mechanical efficiency
B. overall efficiency
C. indicated thermal efficiency
D. volumetric efficiency
35. The increase of efficiency of a compression ignition engine, as the load decreases, is due to
A. higher maximum temperature
B. qualitative governing
C. quantitative governing
D. hit and miss governing
36. A turbo-jet does not require a turbine to drive the compressor.
A. True
B. False
37. For the same maximum pressure and heat input, the exhaust temperature of petrol engine is __________ than that of diesel engine.
A. less
B. more
38. The compression ratio in petrol engines is kept low as compared to diesel engines because higher compression ratio in petrol engines would lead to pre-ignition of fuel.
A. Agree
B. Disagree
39. The cetane (C16H34) which is a straight chain paraffin is assigned a cetane number of
A. 0
B. 50
C. 100
D. 120
40. Morse test is used to determine the I.P. of a
A. single cylinder petrol engine
B. four stroke engine
C. single cylinder diesel engine
D. multi-cylinder engine