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2015(W1(fl)06fl1(b 12U
echanical Engineering for AE KWA (13/02/16) 5 SSC Junior Engineer(20112/2015) ,Asst Transport Officer-KSRTC (07/01/2016) ACE KARUNAGAPPALLY 7034199928, 9037199928, www.aceonIinebooks.com -
Thermodynamics 1 Thermal power plant works on aCarnot cycle b Rankine cycle c Joule cycle d Brayton cycle 2.lf a heat engine attains 100% thermal efficiency,it violates (a)zeroth law of thermodynamics b)first law of thermodynamicsof law of thermodynamics (d)all of the above 3.When a process undergoes a complete cycle then the change of entropy will be a +ve value b -ye value c zero value d +ve or -ye depending on initial condition 4.Stirling and Ericsson cycles are (a reversible cycles b irreversible cycles c quasi-static cycles d semi-reversible cycles 5.Change in enthalpy in a closed system is equal to heat transferred if the reversible process takes place at constant a pressure b temperature c volume d entropy 6.For reversible adiabatic process, change in entropy is
a maximum b minimum c zero d negative 7.Absolute zero pressure will occur a)at sea level b at a temperature of 2730C c under vacuum conditions d when molecular momentum of the system becomes zero
energy loss due to friction is called aadiabatic process b isentropic process c reversible process d irreversible process
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83he expression Jpd v can be used for obtaining work of aEn-flow reversible process badyflowreversible process irreversible ~ ciabatic process (d)all the above 9.An ideal gas at 27°C is heated at constant pressure till its volume becomes three times. The temperature of gas then will be a 81°C b 900°C c627°C d 927°C 10.lf a system after undergoing a series of processes, returns to the initial state then (a)process is thermodynamica Ily in equilibrium (b)process is executed in closed system cycle (c)its entropy will change due to irreversibility (d)sum of heat and work transfer will be zero 11.A process which undergoes
12.ln a Carnot engine,when the working substance rejects its heat to sink,the temperature of sink a increases bdecreases C remains same d none of the above 13.Total heat of a substance is also known as a internal energy b entropy c thermal capacity d enthalpy 14.For which of the following substances, the gas laws can be used with minimum error a~ d rysteam bwet steam csaturated steam jd)superheated steam 15.1f heat be exchanged in a reversible manner, which of the following property of the workin9 substance will change accordingly a temperature (b )enthalpy c internal energy (d)entropy 1 6.The law PV is not applicable for (a)adiabatic expansion of steam
in turbine (b)adiabatic expansion of steam in reciprocating steam engine c)ideal compression of air d)free expansion of an ideal gas 17.Efficiency of a Camot engine with ti200°C, f2300C is a85% b 36% cj8O% d12%
203he hyperbolic process is overned by a Boyle's law b Charie's law c)Gay-Lussac law d)Joule's law 21 .The general law of expansion or compression is pv'1 =C.The process is said to be hyperbolic, if n is equal to
la bO ci d?
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ACE KARUNAGAPPALLY 7034199928, 9037199928, www.aceonIinebooks.com -
1 Out of these one is not non-conventional soure of energy? aWind power b Tidal power c Solar power d Nuclear power 2.Surge tank is not required in head plant a Low b Medium c High d noneofthese 3 . ............. type generator used in wind mill station a Cylindrical b Salient pole c Induction d none of these 4. Load factor is defined as: al Peak load / connected load b Connected load / Peak load cAverage Load/Peak load d Peak load/Average load
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5. Graphite is used in nuclear plant asa ......... a) Fuel b Coolant c) Electrode d Moderator 6.Solar cells are made.............
aSilicon b Germanium c Cadmium d Aluminium
a) Hydro electric b Thermal c) Nuclear d wind mill
7. The fuel used in the nuclear power plants is..... aCoal b Diesel c Uranium d Gas
1 2.Water hammering is more felt in...............HEPP a High head (b) medium head c low head (d) none of these
8. Sag of the transmission line depends upon ............ a The tension of the conductor b The mate ri al of the conductor c Height of the tower d All the factors
13. The highest pointon the daily load curve represents a Average demand b maximum demand c Peak demand d load factor
9. Demand factor is the ratioof.... (a) Average demand / Maximum demand (b)Maximum demand I connected load (c)Connected load / Maximum demand (d) Maximum demand/Average demand
14. Generators used in power plants are...........connected a star b Delta c Star or Delta d Scott
10.For high head and low dischar9e ...............water turbine is used a Pelton wheel b Kaplan c Francis d Propeller
1 6.What is Ferranti effect? Receiving end voltage > Sending end voltage Receiving end voltage< Sending end voltage (c)Receiving end voltage Sending end voltage (d) none of these
11.Spillways are provided in type power plants
1 5.What is the unit of expressing rating of alternator? akW bkVA c kVAR d watt
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23.The heat energy stored in the gas and used for raising the temperature of the gas is known 1 8.The temperature at which the as volume of a gas becomes zero (a )external energy is called b internal energy aabsolute sca le temperature c kinetic energy b absolute zero temperature d molecular energy c absolute temperature d none of the above 24.A pressure gauge reads 1.80 bar when the barometer has a 19.Centrifugal pump is an reading of 755mm of Hg.What is example of the absolute pressure aisolated system a 1.81 bar b closed system b 1.8 bar c steady flow system c 2.81 bar d none of the above d none of these
Electrical Engineering for AE-Electrical, SSC Junior Engineer (20/12/2015) Meter readerIKSEBJ Power System
22,ln a reversible cycle, the source temperature is and the sink temperature is .The maximum available work for a heat input of 1 O0kJ will be 100kJ b 6OkJ OkJ d88kJ
17. Load flow study carried out for.................... (a) to know transformer and line loads b Fault calculation c System planning d A l the above 18. Opening time of .........fuse is minimum a Kitkat b HRC c Cartridge d Oil fuse
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19. A line which connects a consumer and distributor is called a Feeder b Distributor c Service main d none of the above 20.The most clean power plant is a Nuclear power plant b Steam power plant c Diesel power plant d Hydro electric power plant 21 .AnAC secondary distribution system employs 415/ 240,3phase 4wire system 6.6 kV,3phase 3wire system ,
25.ln a throttling process (a)the fluid must undergo an increase in entropy (b)the fluid must undergo a decrease in entropy (c)the entropy may increase or decrease (d)none of the above 26.A close balloon containing 10kg of helium receives 5kJ/kg of heat.During this process,the volume of the balloon slowly increases by at constant pressure of 1 OOkPa.The change in internal energy,in kJ,is
c 3.3 kV.3phase 3wire system d 11kV ,3phase 3wire system
aiO c30
b20 d70
27.The food compartment of a refrigerator is maintained at 4°C by removing heat from it at a rate of 360kJ/min.lf the required power input to the refrigerator is 2kW,the COP of the refrigerator is a2 bi/3 cO.5 d3.0
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28.For a 4S diesel engine,the compression ratio is 21:1 and the cut-off ratio is 2:1 What is its expansion ratio? a 7:1 b 10.5:1 c 12:1 d 19:1
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29.A reversible heat engine working at the rate of 100kW has an efficiency of 20%.The magnitudes of heat transfer rate from the source and to the sink in kW would be,respectivel a 200,100 b 300,20 c 500,400 d 1000,900 30.The boiling and freezing points for water are marked on a temperature scale P as 130 Op and -20 °P respectively. What will be the reading on this scale corresponding to 60 ofl on Celsos oc
a 6(" b 7' c 90 F d 110 F
Answers i(b 2(c) 3c) 40 5(a 6(c) 7d) 8io 9(c) lOd 1 d) 12c 1d 14d 15dJ 16d) 17b) 18b 19c 20a) 21c) 22c 23b 24c) 25a)26c 27d 28b) 29c) 30 ti~
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22. The type of insulators used in stay wires are l al Pin type b Suspension Type c Shackle type d Egg type insulators 23.The only advantages of corona is that it (a)Works as safety valve for surge (b) make line current non sinusoidal (C) betrays its presence by hissing sound (d) producesa pleasing luminous glow 24.The presence of earth in case of over head lines: a increase the capacitance b decrease the capacitance c decrease the inductance d increase the inductance 25.The phenomenon corona is accompanied by the production of: (a Hydrogen (b) Ozone C Nitrogen (d ) None of these 26.Gaurd rinas are used in transmission line to protect it from Overvoltage a~Lightnin? Unequa voltage across the ~ discs (d) corona
27.Buchholz relay is used for the protection of.......... a Generator from external fault b Power transformers from internal faults Generator from intemal fault Power transformers from external faults
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28.Transmission lines are protected from lightning using.... a Surge diverters b Ground wire c Guard ring d Lightning arresters 29.Ferranti effect is 1j0 10 a Line inductance bLine Capacitance c Line Resistance d Line impedance 30.The most economical area of cross section of conductor can be found using .......law a Kirchhoffs law bAmperes law c Kelvin's law d Lenz's law
Answers 1(d) 5d 9b 1 17c 21a 25(b) 29 b
2(a) 6a 1 (a) i4a 18b 22d 26c 30 c
3(c) 7c 1 (a) 15b Rc a) b
4(c) 8d 1 (a) i6a 20d 24a 28 b