1. Main objective of boiler trial is ? a) To determine the generating capacity of the boiler b) To determine the thermal efficiency of the boiler, when working at a definite pressure c) To prepare heat balance sheet for the boiler d) All of the above Ans. d 2. Device used to put off fire in the furnace of the boiler, when the level of water in the boiler falls to an unsafe limit, is ? a) Safety valve b) Fusible plug c) Blow off cock d) Stop valve Ans. b 3. The shell of the cochran boiler is made hemispherical ? a) To provide maximum strength and space b) To withstand high pressure inside c) Both ( a ) and ( b ) d) None of these Ans. c 4. The dryness fraction of steam within a turbine is not allowed to fall below ? a) 0.5 b) 0.9 c) 0.95 d) 0.99 Ans. b 5. With increase in pressure ? a) Enthalpy of dry saturated steam increase b) Enthalpy of dry saturated steam remains same c) Enthalpy of dry saturated steam decreases d) Enthalpy of dry saturated steam first increase and then decrease
1. Which of the following statements is FALSE about double-pass condensers? a) The water flows in one direction through some tubes and returns through the remainder b) Exhaust steam flows through the tubes, while cooling water passes over the outer surface of the tubes c) It is a type of surface condenser d) Cooling water doesn’t come in contact with the exhaust steam Ans. b 2. Which of the following statements is False about steam condensers? a) Jet condensers are cheaper than surface condensers b) Cooling water comes direct contact with the exhaust steam in jet condensers c) Cooling water does not come in direct contact with exhaust steam in surface condensers d) Jet condensers are further classified into single-pass and double-pass condensers Ans. d 3. Which of the following statements is TRUE about single-pass condenser? a) It is a type of jet Condenser b) The flow of water is in one direction only c) The water flows in one direction through some tubes and returns through the rema