Test Bank For Grob's Basic Electronics All Chapters - 9781265468002

AE05 BASICnELECTRONICS


TYPICAL QUESTIONS & ANSWERS
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PARTn-nI
OBJECTIVE TYPE QUESTIONS
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EachnQuestionncarriesn2nmarks.

Choosencorrectnornthenbestnalternativeninnthenfollowing:

Q.1 Thenbreakdownnmechanismninnanlightlyndopednp-nnjunctionnundernreversenbiasednconditionnisncalled
(A) avalanchenbreakdown.
(B) zenernbreakdown.
(C) breakdownnbyntunnelling.
(D) highnvoltagenbreakdown.

Ans:nA

Q.2 Inn anCEn–nconnectedn transistornamplifiernwithn voltagen–
n gainn Av,n then capacitancen Cbcn isn amplifiedn bynanfactor

(A) A v (B) 1nn A v
(C) 1nn A v (D)n An2v

Ans:nB

Q.3 Fornanlargenvaluesnofn|VDS|,nanFETn–nbehavesnas
(A) Voltagencontrollednresistor.
(B) Currentncontrolledncurrentnsource.
(C) Voltagencontrolledncurrentnsource.
(D) Currentncontrollednresistor.

Ans:nC

Q.4 Removingnbypassncapacitornacrossnthenemitter-legnresistorninnanCEnamplifierncauses
(A) increaseninncurrentngain. (B)ndecreaseninncurrentngain.
(C)n increaseninnvoltagengain. (D)decreaseninnvoltagengain.

Ans:nD

Q.5 Fornannop-ampnhavingndifferentialngainnAvnandncommon-modengainnAcnthenCMRRnisngivennby
(A) A v n nAc (B)n A v
Ac
A Anc
(C) v n n1nA (D)
c Av

Ans:nB

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Q.6 Whennanstep-inputnisngivenntonannop-ampnintegrator,nthenoutputnwillnbe
(A) anramp.
(B) ansinusoidalnwave.
(C) anrectangularnwave.
(D) antriangularnwavenwithndcnbias.

Ans:nA

Q.7 HysteresisnisndesirableninnSchmitt-trigger,nbecause
(A) energynisntonbenstored/dischargedninnparasiticncapacitances.
(B) effectsnofntemperaturenwouldnbencompensated.
(C) devicesninnthencircuitnshouldnbenallowedntimenfornsaturationnandndesaturation.
(D) itnwouldnpreventnnoisenfromncausingnfalsentriggering.

Ans:nC

Q.8 Innanfull-wavenrectifiernwithoutnfilter,nthenripplenfactornis
(A)n 0.482 (B)n1.21
(C)n1.79 (D)n2.05

Ans:nA

Q.9 AnmintermnofnthenBoolean-function,nf(x,ny,nx)nis
(A) xnn ynn z (B) xnynz
(C) xnz (D)n(yn+z)nx

Ans:nB

Q.10 Thenminimumnnumbernofnflip-flopsnrequiredntonconstructnanmod-75ncounternis
(A)n5 (B)n 6
(C)n7 (D)n8

Ans:nC

Q.11 Spacenchargenregionnaroundnanp-nnjunction
(A) doesnnotncontainnmobilencarriers
(B) containsnbothnfreenelectronsnandnholes
(C) containsnonentypenofnmobilencarriersndependingnonnthenlevelnofndopingnofnthenpnornnnr
egions
(D) containsnelectronsnonlynasnfreencarriers

Ans:nA

Q.12 Thenimportantncharacteristicnofnemitter-followernis
(A) highninputnimpedancenandnhighnoutputnimpedance
(B) highninputnimpedancenandnlownoutputnimpedance
(C) lowninputnimpedancenandnlownoutputnimpedance
(D) lowninputnimpedancenandnhighnoutputnimpedance

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Ans:nB

Q.13 InnanJFET,natnpinch-offnvoltagenappliednonnthengate
(A) thendrainncurrentnbecomesnalmostnzero
(B) thendrainncurrentnbeginsntondecrease
(C) thendrainncurrentnisnalmostnatnsaturationnvalue.
(D) thendrain-to-sourcenvoltagenisnclosentonzeronvolts.

Ans:nC

Q.14 Whennannamplifiernisnprovidednwithncurrentnseriesnfeedback,nits
(A) inputnimpedancenincreasesnandnoutputnimpedancendecreases
(B) inputnandnoutputnimpedancesnbothndecrease
(C) inputnimpedancendecreasesnandnoutputnimpedancenincreases
(D) inputnandnoutputnimpedancesnbothnincrease

Ans:nD

Q.15 Then frequencyn ofn oscillationn ofn an tunnel-
collectorn oscillatorn havingn L=n 30µHn andn Cn =n 300pfn isnnearby
(A) 267nkHz (B)n 1677nkHz
(C)n1.68nkHz (D)n 2.67nMHz

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Ans:nB fon   n1677n .42nKHz
2 Lc 2 30nnn300n n10n12

Q.16 Thenopen-loopngainnofnannop-ampnavailableninnthenmarketnmaynbenaround.
(A)n10–1 (B)n 10
(C)n 105 (D)n 102

Ans:nC

Q.17 Then controln terminaln (pin5)n ofn 555n timern ICn isn normallyn connectedn ton groundn throughn an capacitorn(
~n0.01µF).nThisnisnto
(A) protectnthenICnfromninadvertentnapplicationnofnhighnvoltage
(B) preventnfalsentriggeringnbynnoisencouplednontonthenpin
(C) convertnthentriggerninputntonsharpnpulsenbyndifferentiation
(D) suppressnanynnegativentriggeringnpulse

Ans:nB

Q.18 Thenvaluenofnripplenfactornofnanhalf-wavenrectifiernwithoutnfilternisnapproximately
(A)n 1.2 (B)n 0.2
(C)n 2.2 (D)n 2.0

Ans:nA
Q.19 ThenthreenvariablenBooleannexpressionnxyn+nxyzn+n xnyn+nxnynz

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(A) ynn xz (B) xnnyz
(C) ynnxz (D) ynnxz

Ans:nC
y(xnnx)nnxz(nynn y)nn ynnxz

Q.20 Thenfan-outnofnanMOS-logicngatenisnhighernthannthatnofnTTLngatesnbecausenofnits
(A) lowninputnimpedance (B)nhighnoutputnimpedance
(C)n lownoutputnimpedance (D)nhighninputnimpedance

Ans:nD

Q.21 Innannintrinsicnsemiconductor,nthenFermi-levelnis
(A) closerntonthenvalencenband
(B) midwaynbetweennconductionnandnvalencenband
(C) closerntonthenconductionnband
(D) withinnthenvalencenband

Ans:nC

Q.22 Thenreversen–nsaturationncurrentnofnansiliconndiode
(A) doublesnforneveryn10Cnincreaseninntemperature
(B) doesnnotnchangenwithntemperature
(C) halvesnforneveryn1Cndecreaseninntemperature
(D) increasesnbyn1.5ntimesnforneveryn2Cnincrementninntemperature

Ans:nA

Q.23 Thencommonncollectornamplifiernisnalsonknownnas
(A) collectornfollower (B)n Basenfollower
(C)n Emitternfollower (D)n Sourcenfollower

Ans:nC

Q.24 Innclass–Anamplifier,nthenoutputncurrentnflowsnfor
(A) anpartnofnthencyclenorntheninputnsignal.
(B) thenfullncyclenofntheninputnsignal.
(C) halfnthencyclenofntheninputnsignal.
(D) 3/4thnofnthencyclenofntheninputnsignal.

Ans:nB

Q.25 Innannamplifiernwithnnegativenfeedback
(A) onlynthengainnofnthenamplifiernisnaffected
(B) onlynthengainnandnbandwidthnofnthenamplifiernarenaffected
(C) onlyntheninputnandnoutputnimpedancesnarenaffected

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