Basic Electrical Engineering VIVA Questions PDF

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*(Basic Electrical Engineering) * *VIVA VOCE *EXPERIMENT ‐1 TO VERIFY KVL AND KCL IN GIVEN CIRCUIT1) Difference between loop and mesh? Ans. Loop : A loop ** is a closed path in a circuit where two nodes are not traversed twice except the initial point, which is also the final one. But in a *loop * o...

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(BasicElectricalEngineering) VIVAVOCE  EXPERIMENT‐1TOVERIFYKVLANDKCLINGIVENCIRCUIT  1)Differencebetweenloopandmesh? Ans. Loop:Aloopisaclosedpathinacircuitwheretwonodesarenottraversed twiceexcepttheinitialpoint,whichisalsothefinalone.Butinaloopother pathscanbeincludedinside. Mesh:Ameshisaclosedpathinacircuitwithnootherpathsinsideit.Inother words,aloopwithnootherloopsinsideit.  2)Whatisopencircuitandshortcircuit? Ans.Opencircuit‐Anincompleteelectricalcircuitinwhichnocurrentflows. shortcircuit‐anelectricalcircuitinadeviceoflowerresistancethanthatofa normalcircuit,especiallyoneresultingfromtheunintendedcontactof componentsandconsequentaccidentaldiversionofthecurrent.  3)WhatisthemaindifferencewhileapplyingKirchhoff’slawind.canda.c circuits?  Ans.ForDCcircuits,analgebraicsumisrequired.ForACcircuits,aphasorsum isrequired.  ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ EXPERIMENT‐2TOVERIFYSUPERPOSITIONTHEOREM 1)Whatisthenatureofcircuitonwhichsuperpositiontheoremcanbe applied?  Ans.theSuperpositionTheoremworksonlyforcircuitsthatarereducibleto series/parallelcombinationsforeachofthepowersourcesatatime(thus,this theoremisuselessforanalyzinganunbalancedbridgecircuit).    ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐   

EXPERIMENT‐3TOVERIFYMAXIMUMPOWERTRANSFERTHEOREM 1)Whatisloadmatching? Ans.Thevaryingoftheimpedanceofaloadcircuit,soastomatchthatofa source.Thishelpsinsurethatthemaximumpossiblepoweristransferredfrom sourcetoload.  2)Whatismaximumpowertransferformula? Ans. Powerdeliveredtotheloadresistance 3)Whatisthereasonthatterminalvoltageislessthanemf? Ans. Becauseemfisthepotentialdifferenceacrossthetwoterminalsofavoltage sourcewhenitisnotconnectedtoanycircuit.Andonceitisconnectedtoa circuit,thevoltagereducesslightlybecauseoftheinternalresistanceofthe voltagesource.  4)Whatistheresistanceofidealvoltagesource? Ans.Areal‐worldvoltagesourcehasaverylow,butnon‐zerointernal resistance&outputimpedance:oftenmuchlessthan1ohm.Conversely,a currentsourceprovidesaconstantcurrent,aslongastheloadconnectedto thesourceterminalshassufficientlylowimpedance.  5)Howistheammeterconnectedinthecircuit? Ans.anammeterisconnectedinserieswithadevicetomeasureitscurrent.  6)Tofindthevoltagedropacrossaresistor,whereshouldthevoltmeterbe connected?  Ans.Avoltmeterisattachedparalleltotheresistor. ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐  EXPERIMENT‐4TOVERIFYRECIPROCITYTHEOREM. Q1)Canyouapplyreciprocitytheoremforamultisourcenetwork? Ans)Thelimitationofthistheoremisthatitisapplicableonlytosinglesource networksandnotinthemulti‐sourcenetwork.Thenetworkwherereciprocity theoremisappliedshouldbelinearandconsistofresistors,inductors, capacitorsandcoupledcircuits.Thecircuitshouldnothaveanytime‐varying elements. ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐

EXPERIMENT‐5 TOSTUDYANDTHEVENINSTHEOREM. TOSTUDYANDVERIFYNORTON’STHEOREM.  Q1)Towhattypeofnetworknorton’stheoremapplicable? Ans‐NortontheoremisuseforcomplexcircuitoryoucanseeitisuseforDC circuit.

 Q2)WhatisplacedinplaceofvoltagesourceswhilecalculatingtheRN? Ans)Removeallsourcesofemfandreplacethembytheirinternalresistance orifacurrentsourceexists,replaceitwithopencircuit. Q3)Giveanexampleofunilateralcircuit? Ans)Dioderectifieristhebestexampleofunilateralcircuitbecauseitdoes notperformtherectificationinbothdirectionofsupply. Q4)Whatisunilateralcircuit? Ans)Inunilateralcircuits,thepropertyofcircuitchangeswiththechangeof directionofsupplyvoltageorcurrent.Inotherwords,unilateralcircuitallows thecurrenttoflowonlyinonedirection.Dioderectifieristhebestexampleof

unilateralcircuitbecauseitdoesnotperformtherectificationinbothdirection ofsupply. Q5)Giveoneexampleofbilateralnetwork? Ans)Bi‐lateralcircuits Inbilateralcircuits,thepropertyofcircuitdoesnotchangewiththechangeof directionofsupplyvoltageorcurrent.Inotherwords,bilateralcircuitallows thecurrenttoflowinbothdirections. Example‐Transmissionlineisthebestexampleofbilateralcircuitbecause,if yougivesupplyfromanydirection,thecircuitpropertiesremainconstant                 ...