CUSAT CAT 2013 Electronics Sciences Question Paper

8/13/2019 CUSAT CAT 2013 Electronics Sciences Question Paper

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MtTtI;ltTEST BOOKLET No. *-

TEST FOR POST GRADUATE PROGRAMMESELECTROMC SCIENCETi e: 2 Hours Maxi u Marks: 450

INSTRUCTIONS TO CANDIDATES1. You are provided with a Test Booklet and an Optical Mark Reader (OMR) Answer Sheet to arkyour responses. Do not soil the Answer Sheet. Read carefully all the instructions given on theAnswer Sheet.2. Write your Roll Nu ber in the space provided on the top of this page.3. Also write your Roll Nu ber, Test Code, and Test Subject in the colu ns provided for the sa eon the Answer Sheet. Darken the appropriate bubbles with a Ball Point Pen.4. The paper consists of ISO objective type questions. All questions carry equal arks.5. Each question has four alternative responses arked A, B, C and D and you have to darken thebubble fully by a Ball Point Pen corresponding to the correct response as indicated in the exa pleshown on the Answer Sheet.6. Each correct answer carries 3 arks and each wrong answer carries 1 inus ark.7. Space for rough work is provided at the end of this Test Booklet.8. You should return the Answer Sheet to the hwigilator before you leave the exa ination hall.However, you can retain the Test Booklet.9. Every precaution has been taken to avoid errors in the Test Booklet. In the event of any suchunforeseen happenings, the sa e ay be brought to the notice of the Obsewer/ChiefSupenntcndent in writing. Suitable re edial easures will be. taken at the ti e of evaluation, itnecessary.
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1 llllllllllllllliELECTRONIC SCIENCE

The forbidden gap in the energy band of Silicon is(A) 0.1 eV (B) 0.7eV(C) l.leV (D) 2.1 eV

Order of current under reverse bias of a Silicon pn diode is

(A) zero (B) l nano A p(C) 1 icro A p (D) 1 illi A pWith reverse bias voltage reverse cuirent in pn diodes varies

(A) linearly (B) exponentially(C) logaritl ically (D) negligiblyCurrent conducted by a Si pn diode under 0.3 V forward bias is of order(A) zero (B) icro A ps

(C) illi A ps (D) depends on te peratureThe relationship of current through a Si pn diode and forward bias voltage is(A) linear (B) exponential(C) circular (D) inversely proportionalA Zener diode conducts cxnrent

(A) in both directions (B) only in forward direction(C) under constant voltage (D) in pulsesA Si junction diode exhibits properties of

(A) resistance only (B) capacitance(C) inductance (D) current source
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2 IIIIIIIIIISi devices can be used only upto a frequency of(A) 1 MHz (B) 10 MHz(C) 100 MHz (D) 1 GHzThe nu ber of junctions in a transistor is(A) one (13) two(C) three (D) fourNu ber of junctions in a tunnel diode is(A) one (B) two(C) three (D) fourSource current in a MOSFET depends on the voltage between

(A) source and drain(C) drain and gate (B) source and gate(D) supply voltageIn a BIT, power gain is axi u in the configuration

(A) Co on Collector(C) Co on Base (B) Co on E itter(D) CascodeIn a CB, RC coupled transistor a plifier low frequency cut off is deter inedby

(B) e itter bypass capacitor(D) bias net work(A) coupling capacitor(C) collector resistanceInput i pedance of co on collector a plifier is

(A) high(C) low (B) oderate si ilar to CE(D) zero
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3 l lflllllllflflllllliWhen co pared to BJ T, FET frequency response is

(A) wider(C) sa e (B) narrower(D) depends on the circuitTe perature can be sensed using

(B) transistor(D) F ET(A) only a ther ocouple(C) copper stripIn a CB transistor, collector current changes by 1 A for a base currentchange of 10 icro a p. This can give the hybrid para eter

(A) hoe =100 ho(C) hfe =l00 (B) hre "100(D) hie =l00 ohA transistor a plifier has a voltage gain of lo. With negative voltage feedback of feed back ratio 0.001, its bandwidth will be(A) sa e (B) s aller(C) larger (D) not related tofbAn SCR conducts current of 200 A when its gate voltage is 4 volt wrtcathode. If the gate voltage falls to 2 volt, the collector current will be

(A) 200 A(C) 50 A (B) 100 A(D) zeroA TRIAC is a device which can used to

(A) a plify low frequency signals(B) control power(C) produce square waves(D) a plify signals at high fiequencies
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4 IllfllllllllA source delivers axi u power at lA p into a load. Its internal resistanceis 10 oh s. Its voltage output

(A) cannot be deter ined(C) will be 10 volts (B) will be arbitrary(D) will be 20 voltsA DC source 10 volts is connected to a series co bination of 10 oh and a1 Farad capacitor. The current through the circuit at 10 secs after switching onwill be

(A) zero A p(C) lA p (B) 0.66 A p(D) infinityAn AC source 10 volts, 1590 Hz is connected to a series co bination of10 oh and a 1 Farad capacitor. The current through the circuit at 10 secs alterswitching on will be

(A) zero A p(C) 1Arnp (B) 0.66 A p(D) infinityAn AC source 10 volts, 1590 Hz is connected to a series co bination of10 oh , a 1 icroFarad capacitor and a 10 illi Henry inductance. Thecurrent through the circuit at 10 secs after switching on will be

(A) zero A p(C) lA p (B) 0.66 A p(D) infinityAn AC source 10 volts, 1590 Hz is connected to a parallel co bination of 10oh , a 1 icroFarad capacitor and a 10 illi IIeniy inductance. The currentthrough the circuit at 10 secs after switching on will be

(A) zero A p(C) 1A p (B) 0.66 A p(D) infinity
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5 INIIIIIIIHIWAn AC source 10 volts, 1590 Hz is connected to a series co bination of a1 icroFarad capacitor and a 10 illi Henry inductance. The current throughthe circuit at 10 seconds after switching on will be

(A) zero A p(C) 1A p (B) 0.66 A p(D) infinityAn AC source 10 volts, 1590 Hz is connected to a parallel co bination of a1 icroFarad capacitor and a 10 illi Henry inductance. The current throughthe circuit at 10 seconds after switching on will be

(A) zero A p (B) 0.66 A p(C) lA p (D) infinityA ideal voltage source has to provide to a load varying fro 120 oh to1500 oh . Its inte al i pedance should be

(A) zero oh s(C) Sq Rt of 120 1500 olnn (B) 120 oh or 1500 oh(D) infinitySound waves propagate in free space with a velocity of

(A) 1500 11]./S(C) light (B) 3 X 10000 /s(D) zero in/sRadio frequency waves propagate in free space with it velocity

(A) proportional to their frequency(B) equal to that of light(C) depending on pennitivity(D) proportional to power radiatedWavelength corresponding to 8.2GHz is

(A) 36.6 c(C) 0.366 c (B) 3.66 c(D) 366c
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6 lllllllfllllRadio Frequency Signals are capable of propagating through Earth with avelocity

(A) of light(C) zero (B) of light but get attenuated(D) infinityA signal at 1 MHz and another at 3 MHz are travelling through the sa econductor. The result will be a signal at

(A) (1 + 3) MHz(C) 1 MHz and 3 MHz (B) (3 1) MHz(D) 4 MHz and 2 MHzModulation of audio signals over high frequency carrier is required because

(A) efficiency of audio is low(B) audio cannot cover large distances due to attenuation(C) high frequency carrier can travel long distance(D) high frequency can easily be generatedIn a plitude odulation, odulated signal co prises

(A) carrier, upper and lower side bands(B) upper sideband(C) lower sideband(D) upper and lower sidebandAn AM trans itter radiates 15 k watts power. If odulation is 100%, powerin lower sideband is(A) 1.25 kW (B) 2.5 kw(C) skw (D) 10kWA single sideband AM trans itter radiates 10 kW. The power at carrierfrequency is

(A) 5 kW(B) 2.5 kW(C) zero(D) s all, only pilot carrier power
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7 llllllflllfllfllifllFrequency odulation results in a signal wlrich needs larger band width thantwice odulating signal. This state ent is TRUE

(A) always(B) for large power signals only(C) for s all odulation index(D) for large odulation indexFrequency odulated signals can be radiated only by

(A) vertical dipoles(B) horizontal dipoles(C) Yagi antennas(D) Any of theseWhen co pared to AM of equal power, FM coverage is

(A) always less (B) always larger(C) li ited by line of sight (D) all roundAntennas to receive FM trans ission are

(A) verticaly polarised (B)(C) circularly polarised (D) horizontally polarisedso eti es directionalRADAR uses icrowave frequencies since

(A) large power can be generated(B) directional radiation can be achieved easier(C) interfelence is ini al(D) range accuracy is goodFor icrowave frequencies ost appropriate trans ission lines are

(B) shielded cables(D) fibre(A) two wire open lines(C) wave guides
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8 IWIIIIIWFor propagation at icrowave frequencies a wave guide allows frequencies

(A) higher thanacut off(C) of all ranges (B) lower than a cut off(D) which are resonantA rectangular wave guide has di ensions l.Sx0.5 c s. It can supportpropagation of icrowave signals at

(A) 1GHz(C) 10 GHZ (B) 5 GHz(D) visible light frequenciesThe ain purpose of the helix in a TWT is to

(A) reduce axial velocity of RF field(B) ensure broad band operation(C) prevent electron bea front spreading(D) reduce noise figureGUNN diode is a device

(A) for switching(C) rectifying icro waves (B) generating square waves(D) generating icro wavesThe type of odulation possible at icro wave frequencies is

(A) AM(C) pulse odulation (B) FM/PM(D) all typesShielded cables are used at high frequencies to

(A) opti ise power transfer(C) protect cable fro bending (B) ini ise radiation(D) ini ise VSWR
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9 llllflllfllllflfllllllllMicrowave frequencies are used for satellite co unication because they

(A) need devices s all in size(B) can penetrate through ionosphere(C) can travel with velocity greater than light velocity in free space(D) are unaffected by noiseAn a plifier shows a gain of 1000 at 4 kHz, 707 at 7.1 kHz and at 100 Hz. Itsbandwidth is(A) 4kHz (13) 7kHz(C) 7.lkHz (D) 100 HzA sy etric two port network has series ar s and shunt ar 120 oh s. Thenits characteristic i pedance is

(A) 60_oh s(C) 240 oh s (B) 120 oh s(D) 360 oh sTwo resistances R1 and R2 are connected in parallel across a battery of 6 Vwith internal resistance R0. R1 is found to dissipate 3 watts while R2dissipates half of this value. Then R0 =(A) 0.5 oh (B)(C) 1.5 oh 1 oh(D) 2 ohA 10 oh resistance is connected in series with an inductance L=l00 lIenryand a capacitance C = 0.1 icro Farad to a 10 V, ac source. At a frequency of1590 Hz the resistance dissipates 10 Walls. At a frequency of 3180 Hz. theresistance dissipates

(A) 5 watts (B) less than 10 watts(C) 10 Watts (D) 20 watts
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10 IIHIIIIIA 10 oh resistance is connected in series with an inductance L=l 00 fle yand a capacitance C = 0.1 icro Farad to a 10 v, ac source. At a frequency of1590 Hz the resistance dissipates 10 Watts. The voltage across the inductanceat this frequency is(A) less than 10 v (B)(C) 50 v (D) 10v100vA 10 oh resistance is connected in series with an inductance L=i0O Hcnryand a capacitance C = 0.1 icro Farad to a 10 v, ac source. At a frequency of1590 Hz the resistance dissipates 10 Watts. The voltage across the resistanceat this frequency is(A) less than 10 v (B)(C) 50 v 10 V(D) 100 vA current 1 A p passes through an inductance L = 1 H. The energy stored inL is

(A) 0.5 J(C) 0.5 I if current is DC (B) 0.5 I if current is AC(D) zeroA current 1 A p passes through an inductance L = I H. The power dissipatedin L is

(A) zero Watt(C) lWatt (B) 0.5 Watt(D) 2WattIn an RC coupled transistor CE a plifier, an unbypassed e itter resistancewill lead to

(A) shift in quiescent point(C) fail in output i pedance (B) fall in input i pedance(D) reduction in gain
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11 iflfllfl llfllllllThe ain disadvantage of CW Doppler radar is that

(A) it does not give target velocity(B) it does not give target range(C) a transponder is required at target(D) All of the above are disadvantagesWhat is the ost noticeable effect of a s all increase in te perature in theco on e itter connected BIT?

(A) Increase in output resistance(B) Increase in lg50(C) Increase in forward current gain(D) Decrease in forward current gainWhen co pared with a BJT a plifier the input i pedance of an FETa plifier stage is(A) sa e (B) s aller(C) larger (D) 10% largerA thin base region in a transistor will provide

(A) larger power (B) larger current gain(C) s aller gain (D) higher speedIncreasing the doping concentration in a pn diode will lead to(A) tunneling (B) Zener effect(C) break down (D) ther al stabilityIn an 11 type MOSFET the ajority carriers are(A) electrons (B) holes(C) electrons and holes (D) absent
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12 IIIIIIIIIIHIIIn a se iconductor junction with no applied bias, charge carriers

(A) face a potential well(B) ju p fro valence to conduction band(C) fall fro conduction to valence band(0) re ain bound to their parent ato sWhen reverse bias voltage is applied to a Zener diode, electrons on the p side

(A) oppose the bias(C) cross the barrier (B) assist the bias(D) stay on 11 sideIn a tunnel diode electrons on the p side and holes on the 11 side can

(A) cross the forbidden gap(B) pass through the gap to other side(C) pass through the gap to available sites on the other side(D) pass through the gap to available sites on the other side on forwardbiasIn a Reflex Klystron oscillation occurs because

(A) electron bea is highly focused(B) electrons repel each other(C) velocity odulation occurs(D) density odulation occursA transistor like BCIO7 can work at frequencies of order

(A) 2 MHz(C) 200 MHz (B) 20 MHz(D) 2000 MHZMagnetron is a device which provides

(A) high agnetic fields(B) large a plification and oscillation at 100 MHZ. only(C) oscillation at GHz(D) high frequency agnetic field


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13

Open wires cannot be used at frequencies of order 500MHz because(A) this frequency is for ilitary usage(B) wires ust be very thick(C) they get heated due to skin effect(D) radiation losses occur

Microwave devices nor ally work with(A) AC power supply (B)(C) switched power (D)VHF devices need cooling since(A) these are bulky (B)(C) skin effect is present at VHF (D)

In transistors operating speed is li ited by(A) V00 (B)(C) junction te perature (D)

DC power supplyvery high frequency power

these are usually tlrer ionicelectrodes da age

base voltagedoping levelWhen co pared to a BJT the speed perfor ance of an FET is(A) inferior (B)(C) the sa e (D)An LED is a device which can be used to

(A) a plify low frequencies (B)(C) indicate state of signal (D)Devices used in ost digital circuits are(A) transistors only (B)(C) transistors and FETs (D)

superior1.1 ti es better

a plify high frequenciesprovide audio alar

FETs onlyLCDs
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79.

80.

82.

85.

14 IIIIIIIIIBinary digital circuits as in co puters use(A) Os and is (B)(C) On OFF relays two level voltages(D) SCRsMost digital circuits operate with Vcc of 5 volts since

(A) 5V is easily generated fro batteiy(B) ost ICs are anufactuzed for SV(C) noise argin is good(D) 0 and 1 are 0V and 5V, as per international standardsA and B are binary variables. Then A + A is

(A) 0(C) A (B) 1(D) X(do11t care)A and B are binary variables. Then (A + B) =(A) 0 (B) 1(C) A+B (D) A.BBinary representation of deci al nu ber 14 is

(A) 0001 0100(C) E (B) 1110(D) FWhat is the typical value for the ratio of cunent in a pn junction diode in theforward bias with that in the reverse bias?(A) 1 (B) 10(C) 100 (D) 1000The logic function ABC + AB + ABC is equivalent to(A) A (B) B(C) ABC (D) 1


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87.

89.

90.

15 lflllllflflllflfllA logic circuit which can identify when two variables A and B axe not si ilaris

(A) OR gate(C) EXOR gate (B) AND gate(D) EXNOR gateA logic circuit which can identify when two variables A and B are si ilar is

(A) OR gate(C) EXOR gate (B) AND gate(D) EXNOR gateThe nu ber of bits in a product of two non zero binary nu bers with 5 and 7bits is

(A) 5(C) 7+1In TTL logic circuits the 0 and 1 levels are respectively

(B) 7(D) 5 + 7 1 or ore

(A) below 0 and above 5(B) O and 1 volts(C) 0.8 volts and 3.2 volts(D) 0.8 volts and below and 3.2 volts and above

Twos co ple ent representation is used in co puters to perfor arith eticon(A) + ve and ve deci al nu bers(B) fractions(C) + ve and ve binary nu bers(D) only on floating point nu bers

A floating point representation has(A) +'or sign and value(B) exponent and agnitude(C) biased exponent and agnitude(D) biased exponent and agnitude as fraction


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92.

93.

94.

95.

96.

97.

16 IIIIIIIIIThe range of an 8 bit binary nu ber in icroprocessors can represent therange

(A) 0 255 deci al(C) 0 to 2 power 8 (B) l27to +123(D) 0123Current day icroprocessors work at clock speeds upto

(3)(D)

10 MHZ1 GHZ and above(A) 1MHz(C) 100MHzThe ain e ory of ode day co puters is

(A) se i conductor(C) agnetic Tape (B) agnetic core(D) CCDOne i portant li it to speed of operation of co puters is

(A) access ti e of e ory(B) density of devices in CPU(C) speed of peripherals like printers(D) speed of display devices

Digital co puters can perfor only(A) addition and logic operations(B) addition, logic operations and calculus(C) with the help of algorith s any athe atical operation(D) text processing in addition to all these with suitable codes

The nu ber of distinct ele ents that Boolean algebra can have is(A) 2(C) 4 (B) 3(D) any


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104.

105.

106.

107.

108.

109.

18 lflllfllllThe open loop bandwidth of an opa p like 741 is of order(A) 10 Hz (B)(C) l K Hz (D) 100 Hz100 KIIzThe input i pedance of an opa p is of the order of(A) 100 oh (B)(C) [00 k oh (D) 1 k oh10 M ohAn opa p integrates the input fed at inverting ter inal by connecting in thefeed back path

(A) a suitable resistance(C) a capacitor (B) an inductance(D) diode connected transistorOpa p 741 is connected as unity gain inverting a plifier. Slew rate isspecified as 0.5V/ icrosec. The inverting voltage input changes by 10 Volts.Then the output voltage will change to 10 volts

(A) instantly(B) after 5 1]1iC1O sec(C) after 20 icro sec(D) afier delay depending on the input wavefonn

Cut off frequency of a first order low pass filter for R, :2.5!cQ andC,0.05,uF is(A) 1.273 kHz (B)(C) 127.3 kHz (D) 12.73 kHz127.3 HzAn opa p is connected as an integrator with feed back resistance R andcapacitance C. A square wave is fed to its inverting input. Then the outputwill be triangular wave if input

(A) period is less than '/z.pi. RC(B) period is ore than /2 .pi. RC(C) voltage is g1'cateit'iian eff set(D) voltage is less than off set
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110.

111.

112.

M3.

114.

19 llllllfilllflllllllllllThe output is connected to the inverting input of a 741 opa p. A sinusoidalinput of 1 volt, lkHz is connected to the non inverting input through a10 K oh resistance. The out put is then of the order of

(A) 1 volt, input i pedance 10 k oh(B) 10 volt, input i pedance 10 k oh(C) l volt, input i pedance 100 k oh(D) 1 volt, input i pedance 1 M ohThe output of an opa p integrator is connected to another opa p integratorwhose output is connected back to the first integrator. This will provide anoutput of

(A) highly stable original signal(B) sinusoidal oscillation(C) highly a plified signal(D) perfect integrated inputThe input current drawn by a unity gain opa p like 741 is

(A) 1 icro a p (B) 1 rnilli a p(C) order of collector current (D) negligibleThe output i pedance of an opa p is of the order of

(A) few oh s(C) ega oh s (B) koh s(D) infinityA transistor Co on E itter RC ooupled a plifier has voltage gain of 50 anda current gain of 20. An input signal at 1 volt and current 0.1 illi a p isapplied to this stage. The output power is(A) l ilii watts (B) 10 illi watts(C) 100 illiwatt's (D) distorted


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20 IIIIIIIIIHAn inverting opa p 741 has a closed loop gain of 200. A sinusoidal input 1volt at I k Hz is applied to its inverting input. If the supply voltage is Vcc, theoutput will be

(A) cosinusoidal 10 volt, 1 kHz(B) sinusoidal 200v, 1 kHz(C) near square wave, at Vcc , 1 kHz(D) triangular, Vcc, 1 kHzCathode ray oscilloscopes provide

(A) visual displays(C) deflection of needle (B) audio output(D) both audio and video outputAn electron is released at the botto plate of two parallel plates spaced l cand the upper plate at 200vo1ts with reference to the lower plate. Then theelectron will gain an energy of

(A) 200 eV(B) 5.93 x 200(C) 200 X c ev where c is velocity of light(D) 5.93 X 14.1 eVIn a CRO to observe wave fonns a sawtooth voltage is applied to

(A) vertical deflection plates(B) horizontal deflection plates(C) between cathode and anode(D) the phosphor of the screenIn oscilloscopes with deflection sensitivity l0 V/c the input signal shouldsupply

(A) zero current(B) current proportional to the voltage(C) 1 V for deflection of 1 c(D) 10 V for deflection 1 c


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12].

122.

123.

124.

125.

21 lllllllllllllillllStable wavefor s can be observed on CRO screens if the frequency ofhorizontal sweep input are

(A) sa e(B) related by integer ultiple(C) related by integer ultiple and the screen has persistence(D) related by integer ultiple and the screen has persistence and signallevel is above a thresholdThe solution to si ultaneous equations in two variables requires

(A) one unique equation(B) two independent equations(C) specific boundary.conditions(D) atrix of rank 1Si ultaneous algebraic equations in two variables can be solved usingoperational a plifiers interconnected as

(A) integrators (B) differentiators(C) su ing a plifiers (D) ultipliers.\'(t) is a function of ti e. When differentiated twice gives ICU) as a result.Then x(!) is

(A) a constant(C) =!"*2 (B) = 1(D) sin k t , where at = constantA plifier responses are plotted in log freq Vs gain so that

(A) errors are ini ised(B) frequency scale need not start at zero(C) large frequency range can be covered(D) log is a liner operator

A transistor a plifier has a voltage gain of 100. Its power gain in dB is(A) 10 dB(C) 30 an (B) 20 dB(D) 40 an
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23 IHWHHIIIIIHIIIIA atrix has 4 rows {1,2,3,4} {.5.,2,4,2}, {2,4,6,8}, {s,5,7,o}. Its rank is(A) 4 (B) 3(C) 2 (D) 1The output of a transistor CE a plifier and its input are

(A) in phase(B) out of phase(C) in phase in id frequency(D) out of phase in id frequencyAn L,C,R circuit draws a current of 10 in A at 1 kHz . The current drawn logsthe voltage applied by 30 degrees. Voltage across the resistance R = 10 ohis 10 volts. Power dissipated in the resistance is then

(A) 0.] watt(C) 0.1 X sin 30 (B) 0.1 X cos 30(D) zeroTwo 4 X 4 atrices A and B are ultiplied. The result is an identity atrix.Then

(A) B is transpose of A(C) B is inverse of A (B) A is transpose of B(D) B is hennitian of ATwo atrices can be ultiplied only if

(A) they are both real(B) nu ber of rows of first equals nu ber of colu ns of the second(C) nu ber of colu ns of first e'quals nu ber of rows of the second(D) they are square atricesThe atrix whose off diagnol ele ents are zero

(A) has no inverse(B) is its own inverse(C) has rank zero(D) has rank one less than nu ber of rows
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I42.

I43.

24 IIIMIIIIUHybrid para eters of a CB transistor contains 4 ele ents in two rows whichare

(A) i peda nces(B) voltage ratios(C) two ratios, one i pedance and one ad ittance(D) one voltage ratio, one current ratio, one i pedance and oneconductanceAt high frequencies a CB transistor a plifier exhibits

(A) large attenuation(B) instability(C) large power dissipation(D) phase shift greater than 180 degA syste is described by its transfer function which has poles at 1, +1 andzeros at 0 and 2. The syste is

(A) stable since poles are not greater than 1(B) unstable since zero is at 2(C) unstable due to pole at +1(D) stable since Nyquist criterion is satisfied

An a plifier has a gain of 200. It has a positive feed back of 0. 5. Thissyste will(A) oscillate as Barkhausen criterion is satisfied(B) oscillate because positive feed back exists(C) larger band width than without feed back(D) s aller gain than without feed back

Negative feed back in a plifier circuits introduces(A) instability(B) distortion only(C) stability only(0) stability as also reduces distortion
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25 llllllflllllllllllOscillator circuits will always produce

(A) sinusoidal out put only(B) steady DC plus saw tooth(C) square waves or sinusoidal outputs(D) da ped sine wavesThe Fourier transfor of a steady DC is(A) zero (B) linearly increasing(C) circle (D) pulse at zeroThe Fourier transfor of a ti e function x(t) is

(A) real and sy etric(C) exponential function (B) co plex(D) constantThe Laplace transfonn of a ti e function x(t) = constant, t> = 0 is(A) constant (B)(C) 1 / s + l 1/ is(D) SThe Laplace transfo i of the i pedance of an inductance L at frequency f is,(where w is radian frequency, s is Laplace operator)(A) jwL (B) l/jwL(C) 1lsL (D) sLThe response of a circuit to DC of 1 volt is given by Us + 3. In ti e do ain itis

(A) sin 3:(C) exp (31) (13) DC of? volt(D) EXP ( + 30Transfer function of a syste is given by H = l! (s 2) (s 1) (s + 1). Thesyste is

(A) oscillatoiy(C) stable (B) unstable(D) conditionally stable53!!!!


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CUSAT CAT 2013 Electronics Sciences Question Paper

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