4151. Reaction turbines are used for____________________?
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A. high head

B. low head and high discharge

C. low head

D. high head and high discharge

E. high head and low discharge

4152. The angle of taper on draft tube is A. greater than 15 B. greater than 8 C. greater than 5 D. less than 8 E. less than 3.___________________?
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A. greater than 5

B. less than 3.

C. angle of taper on draft tube is

D. less than 8

E. greater than 8

F. greater than 15

4153. In a single casing, multistage pump running at constant speed, the capacity rating is to be slightly lowered. It can be done by_______________?
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A. trimming the impeller size to the required size by machining

B. designing new impeller

C. none of the above

D. not possible

E. some other alterations in the impeller

4154. For starting an axial flow pump, its delivery valve should be____________________?
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A. closed

B. partly open and partly closed

C. depends on starting condition and flow desired

D. could be either open or closed

E. open
4155. The flow rate in gear pump___________________?
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A. none of the above

B. decreases with increase in pressure

C. unpredictable

D. increases with increase in pressure

E. more or less remains constant with in-crease in pressure
4156. Medium specific speed of a pump implies it is_________________?
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A. axial flow pump

B. any one of the above

C. mixed flow pump

D. centrifugal pump

E. none of the above

4157. The horse power required in above case will be___________________?
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A. 0.75 B.H.P.

B. B.H.P./0.75

C. 1.5 B.H.P.

D. same

E. none of the above

4158. Saving of work done and power by fitting an air vessel to single acting reciprocating pump is of the order of__________________?
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A. 39.20%

B. 49.20%

C. 84.8%

D. 91.6%.

E. 68.80%

4159. Hydraulic accumulator is used for____________________?
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A. accumulating hydraulic energy

B. supplying energy when main supply fails

C. accumulating oil

D. generally high pressures to operate hydraulic machines

E. supplying large quantities of oil for very short duration

4160. Runaway speed of a hydraulic turbine is_________________?
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A. the speed corresponding to maximum overload permissible

B. the speed at which turbine runner will be damaged

C. none of the above.

D. full load speed

E. the speed if the turbine runner is allowed to revolve freely without load and with the wicket gates wide open
4161. Francis, Kaplan and propeller turbines fall under the category of___________________?
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A. Reaction-cum-impulse turbines

B. Mixed flow turbines

C. Reaction turbines

D. Impulse turbines

E. Axial flow turbines

4162. In a centrifugal pump, the liquid enters the pump__________________?
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A. at the top

B. at the bottom

C. at the center

D. none of the above

E. from sides

4163. According to fan laws, for fans having constant wheel diameter, the pressure varies________________?
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A. square root of fan speed

B. directly as fan speed

C. square of fan speed

D. none of the above

E. cube of fan speed

4164. The specific speed of turbine is defined as the speed of a unit___________________?
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A. of such a size that it delivers unit dis-charge at unit power

B. of such a size that it produces unit horse power with unit head

C. none of the above

D. of such a size that it requires unit power per unit head

E. of such a size that it delivers unit dis-charge at unit head

4165. Lancing is the operation of _________________?
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A. cutting a sheet of metal through part of its length and then bending the cut portion

B. cutting a sheet of metal in a straight line along the length

C. removal of metal to the desired shape from the edge of a plate

D. bending a sheet of metal along a curved axis

4166. A file removes the metal during___________________?
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A. both forward and return strokes

B. forward stroke

C. return stroke

D. none of these

4167. A neutral flame is obtained by supplying___________________?
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A. more volume of acetylene and less volume of oxygen

B. none of the above

C. more volume of oxygen and less volume of acetylene

D. equal volumes of oxygen and acetylene
4168. The shrinkage allowance for cast iron pattern is________________?
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A. 15 mm/m

B. 10 mm/m

C. 26 mm/m

D. 20 mm/m

4169. The operation of straightening a curved sheet metal, is known as____________________?
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A. coining

B. planishing

C. squeezing

D. drawing

4170. Tandem drawing of wires and tubes is necessary because_________________?
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A. annealing is needed between stages

B. it is not possible to reduce at one stage

C. accuracy in dimensions is not possible otherwise

D. surface finish improves after every drawing stage

4171. Which of the following statement is wrong ?
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A. all of these

B. The mortise gauge has two scribing pins

C. An auger is a planning tool

D. The gouges are chisels with a hollow shaped blade

4172. The cold working of metals is carried out_________________?
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A. at the recrystallisation temperature

B. below the recrystallisation temperature

C. above the recrystallisation temperature

D. at any temperature

4173. In a _____________ , both cutting and non-cutting operations are performed at one station of the press in every stroke of the ram?
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A. progressive die

B. combination die

C. simple die

D. compound die

4174. In spot welding, the spacing between two spot weld should not be less than _______________?
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A. 1.5d

B. d

C. 3d

D. 6d

4175. In vapour compression cycle, the conditii of refrigerant is saturated liquid________________?
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A. before entering the expansion valve

B. after passing through the expansion throttle valve

C. before entering the compressor

D. after passing through the condenser

E. before passing through the condensei

4176. Most of the domestic refrigerators work on the following refrigeration system _________________?
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A. vapour compression

B. electrolux refrigerator

C. dual cycle

D. carnot cycle

E. vapour absorption

4177. Allowable pressure on high-pressure side or ammonia absorption system is of the order of_________________?
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A. 2-4 bars

B. 7-10 bars

C. 5-6 bars

D. atmospheric pressure

E. slightly above atmospheric pressure

4178. If a heat pump cycle operates between the condenser temperature of +27C and evaporator temperature of 23C, then the Carnot COP will be_________________?
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A. 1.2

B. 6

C. 10

D. 0.2

E. 5

4179. Aqua ammonia is used as refrigerant in the following type of refrigeration system_________________?
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A. compression

B. direct

C. absorption

D. none of the above

E. indirect

4180. In refrigerator, liquid receiver is required between condenser and flow controlling device, if quantity of refrigerant for system is_____________________?
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A. there is no such consideration

B. pone of the above

C. more than or equal to 3.65 kg

D. less than 2 kg

E. more than 10 kg

4181. A refrigerant should have _____________________?
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A. Tow specific heat of liquid

B. low specific volume of vapour

C. k up the wrong statement ?

D. high latent heat of vaporisation

E. higher critical temperature

F. high boiling point
4182. One ton refrigeratiqn corresponds to_________________?
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A. 50 kcal/min

B. 80 kcal/min

C. 80 kcal/hr

D. 50 kcal/kr

E. 1000 kcal/day

4183. A refrigeration cycle operates between condenser temperature of + 27C and evaporator temperature of- 23C. The Cannot coefficient of performance of cycle will be_________________?
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A. 6

B. 5

C. 0.2

D. 10

E. 1.2

4184. Critical temperature is the temperature above which _____________________?
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A. none of the above

B. water will evaporate

C. a gas will immediately liquefy

D. water will never evaporate

E. a gas will never liquefy
4185. The COP of a domestic refrigerator___________________?
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A. is equal to 1

B. depends upon the make

C. is less than 1

D. is more than 1

E. depends upon the weather conditions

4186. The refrigeration effect in a dry evaporator compared to flooded evaporator in a similar plant is_________________?
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A. unpredictable

B. same

C. more or less depending on ambient conditions

D. more

E. less
4187. The evolution of heat of solution takes place in ammonia absorption plant when _____________________?
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A. lithium bromide is driven out of solution

B. lithium bromide mixes with ammonia

C. ammonia vapour goes into solution

D. ammonia vapour is driven out of solution

E. weak solution mixes with strong solution

4188. Vertical lines on pressure-enthalpy chart show constant_______________?
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A. pressure lines

B. volume lines

C. total heat lines

D. temperature lines

E. entropy lines

4189. The C.O.P of a refrigeration cycle with increase in evaporator temperature, keeping condenser temperature constant, will______________________?
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A. increase

B. unpredictable

C. remain unaffected

D. may increase or decrease depending on the type of refrigerant used

E. decrease

4190. Clapeyron equation is applicable for registration at___________________?
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A. saturation point of vapor

B. saturation point of liquid

C. critical point

D. sublimation temperature

E. triple point

4191. Presence of moisture in a refrigerant affects the working of___________________?
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A. expansion valve

B. heat transfer

C. evaparator

D. compressor

E. condenser

4192. For obtaining high COP, the pressure range of compressor should be_______________?
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A. low

B. high

C. any value

D. there is no such criterion

E. optimum

4193. In vapor compression cycle, the condition of refrigerant is very wet vapor________________?
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A. before entering the expansion valve

B. after passing through the condenser

C. before entering the compressor

D. before passing through the condenser

E. after passing through the expansion or throttle valve

4194. The bank of tubes at the back of domestic refrigerator are _________________?
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A. condenser tubes

B. refrigerant cooling tubes

C. capillary tubes

D. evaporator tubes

E. throttling device

4195. For proper refrigeration in a cabinet, if the temperature and vapour pressure difference between cabinet and atmosphere is high, then_________________?
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A. perfectly tight vapour seal should be used

B. smaller cabinet should be used

C. refrigerant with high boiling point must be used

D. refrigerant with lower evaporation temperature should be used

E. bigger cabinet should be used

4196. Vapor compression refrigeration is some what like ____________________?
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A. Rankine cycle

B. reversed Camot cycle

C. none of the above

D. reversed Rankine cycle

E. Carnot cycle

4197. In vapor compression cycle, the condition of refrigerant is high pressure saturated liquid________________?
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A. before entering the expansion valve

B. after passing through the condenser

C. before passing through the condenser

D. before entering the compressor

E. after passing through the expansion or thiottle valve

4198. In S.J. unit, one ton of refrigeration is equal to___________________?
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A. 210 kJ/min

B. 420 kJ/min

C. 840 kJ/min

D. 105 kJ/min

E. 21 kJ/min

4199. Condensing temperature in a refrigerator is the temperature_________________?
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A. at which refrigerant gas becomes liquid

B. of evaporator

C. of freezing zone

D. of cooling medium

E. condensing temperature of ice

4200. Ammonia-absorption refrigeration cycle requires__________________?
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A. none of the above

B. zero work input

C. maximum work input

D. very little work input

E. nearly same work input as for vapour compression cycle