201. The formation of fog starts when,
(A) air temperature is equal to the dew point temperature
(B) air temperature is greater than the dew point temperature
(C) both a. and b.
(D) none of these
Answer: - air temperature is equal to the dew point temperature
202. Work done in a constant volume process is
(A) negative
(B) zero
(C) positive
(D) none of these
Answer: - zero
203. Which processes do occur in the Brayton cycle?
(A) two reversible adiabatic processes and two reversible isochoric processes
(B) two reversible adiabatic processes and two reversible isobaric processes
(C) two reversible adiabatic processes and two reversible isothermal processes
(D) two reversible adiabatic processes and two reversible isentropic processes
Answer: - two reversible adiabatic processes and two reversible isobaric processes
204. When two refrigerating cycles are used in series with two different refrigerants, the system is known as
(A) dual refrigeration system
(B) cascade refrigeration system
(C) vapour absorption refrigeration system
(D) none of these
Answer: - cascade refrigeration system
205. What is the purpose of using economizer in the boiler?
(A) to heat feed water by utilizing heat from exhaust gases
(B) to heat feed water by utilizing some heat from superheated steam
(C) to superheat steam
(D) none of the above
Answer: - to heat feed water by utilizing heat from exhaust gases
206. In a diesel engine, the fuel is ignited by
(A) spark
(B) injected fuel
(C) heat resulting from compressing air that is supplied for combustion
(D) ignition
Answer: - heat resulting from compressing air that is supplied
207. Compression ratio of IC. engines is
(A) the ratio of volumes of air in cylinder before compression stroke and after compression stroke
(B) volume displaced by piston per stroke and clearance volume in cylinder
(C) ratio of pressure after compression and before compression
(D) swept volume/cylinder volume
Answer: - the ratio of volumes of air in cylinder before compression stroke and after compression stroke
208. The ignition quality of petrol is expressed by
(A) Cetane number
(B) Octane number
(C) Calorific value
(D) All of these
Answer: - Octane number
209. Pour point of fuel oil is the
(A) minimum temperature to which oil is heated in order to give off inflammable vapours in sufficient quantity to ignite momentarily when brought in contact with a flame
(B) temperature at which it solidifies
(C) it catches fire without external aid
(D) indicated by 90% distillation temperature i.e., when 90% of sample oil has distilled off
Answer: - temperature at which it solidifies
210. Which of the following is a steam turbine?
(A) De laval
(B) Kaplan
(C) Francis
(D) Pelton
Answer: - De laval
No comments:
Post a Comment