The variation of drain current with gate-to-source voltage of a MOSFET is shown in fig.The MOSFET is (GATE-EE-2003)

The variation of drain current with gate-to-source voltage of a MOSFET is shown in fig.The MOSFET is (GATE-EE-2003) A. an n-channel depletion mode device B. an n-channel enhancement mode device C. a p-channel depletion mode device D. a p-channel enhancement mode device ANSWER:   C It is the transfer characteristics of a depletion mode device and it  must be p-channel, since the Vgs is positive in p-channel depletion regio...

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The steady state error due to step input for a type 1 system is ........ (GATE-EE-1995)

The steady state error due to step input for a type 1 system is ........  (GATE-EE-1995) Answer :  ...

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All the resistances in the figure are 1 ohm each.The value of current 'I' is

All the resistances in the figure are 1 ohm each.The value of current 'I' is  ( GATE-EE-1992) A. 1/15A B. 2/15A C. 4/15A D. 8/15A Answer: Given R = 1, v = 1 After reduction , we get  Req = 1.875 I = 1 / 1.875 = 0.533 = 8/15...

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The uncontrolled electronic switch used in power electronic converter is

The uncontrolled electronic switch used in power electronic converter is (GATE-EE-1998) A. thyristor B. bipolar junction transistor C. diode D. MOSFET Explanatory answer: Thyristor - semi controlled device BJT and Mosfet -fully controlled device Diode - uncontrolled device, since its on/off depends on external circuit.we cannot contr...

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The concept of an electrically short, medium and long transmission line is primarily based on the (GATE-EE-2006)

The concept of an electrically short, medium and long transmission line is primarily based on the   (GATE-EE-2006) A. nominal voltage of the line B. physical length of line C. wave length of line D. power transmitted over the line Ans: Physical length of li...

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A low-pass filter with a cut-off frequency of 30HZ is cascaded with a high-pass filter with a cut-off frequency of 20HZ. The resultant system of filters will function as

A low-pass filter with a cut-off frequency of 30HZ is cascaded with a high-pass filter with a cut-off frequency of 20HZ. The resultant system of filters will function as   (GATE-EE-2011) A. an all-pass filter B. an all-stop filter C. a band stop (band reject) filter D. a band-pass filter  Explanatory answer : Low-pass filter with a cut-off frequency of 30HZ: High-pass filter with a cut-off frequency of 20HZ: The cascade combination...

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An inductor is connected in series with SCR to protect it against

An inductor is connected in series with SCR to protect it against A. damage due high dv/dt B. damage due to high di/dt C. damage due to large forward current D. none of these Explanatory answer : An inductor is connected in series with SCR to protect it against damage due to high di/dt At the instant of turn on, the current flowing through SCR is not distributed uniformly and the rate of rise of current (di/dt) is very fast.This produces localized...

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The transfer function of a system is given as

The transfer function of a system is given as    This system is                                      (GATE-EE-2008) A. an overdamped system B. an underdamped system C. a critically damped system D. an unstable system Explanatory answer: Systems are classified according to their damping ratio( ζ ) vales, If ζ < 1, underdamped...

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An Enhancement tye n-channel MOSFET is represented by the symbol

An Enhancement tye n-channel MOSFET is represented by the symbol   (GATE-EE-1999) Explanatory answer:  The dashed line between drain and source only used in E-mosfet symbol and that is the basic symbol difference between  D-mosfet and E-mosfet . From the given options only option A and B has dashed line, but in n- channel arrow mark will be pointed in,so the correct answer will be option ...

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The colour code of 1K ohm resistor is

The colour code of 1K ohm resistor is   (GATE-EE-1999) A. black,brown,red B. red, brown,brown C. brown,black,red D. black,black,red Explanatory answer:  for Brown :  1 Black   :  0 red       :  2 therefore ,    10*10^2  =  1000K Ans:  brown,black,red ...

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The winding of a 4-pole alternator having 36 slots and a coil span of 1 to 8 is short-pitched by........ degrees.

The winding of a 4-pole alternator having 36 slots and a coil span of 1 to 8 is short-pitched by........ degrees. A.140 B. 80 C. 20 D. 40 Explanatory answer: Pole pitch:                 Centre to centre distance between two adjacent poles                 Pole picth= 180 deg electrical                 Pole pitch= slots/Pole= n Coil span :                The distance between two coil...

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In a 6 pole dc machine,90 mechanical degrees corresponds to ......... electrical degrees.

In a 6 pole dc machine,90 mechanical degrees corresponds to ......... electrical degrees. A. 30 B. 180 C. 45 D. 270 Explanatory answer: The relationship between mechanical and electrical degrees is 1 degree mechanical = (P/2) electrical degrees i.e. for 1 deg of mechanical revolution of conductor inside a magnetic field produces (P/2) degree electrical output. Given, P=6 90 deg mechanical = 90 (P/2) electrical                              = 90*(6/2)    ...

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How much RMS current does a 300W, 200V bulb take from the 200V, 50HZ power lines ?

How much RMS current does a 300W, 200V bulb take from the 200V, 50HZ power lines ? A. 0.5A B. 1.5A C. 2A D. 3A Explanatory answer: P=V^2/R Therefore R= V^2/ P R= 200^2 / 300 R= 133.33 ohm (resistance of lamp) Rms current  taken by lamp = rms value of supply voltage /resistance of  lamp                                          =...

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A 50 HZ alternator will run at the greatest possible speed if it is wound for ...... poles

A 50 HZ alternator will run at the greatest possible speed if it is wound for ...... poles A. 8 B. 6 C. 4 D. 2 Explanatory answer: Ns=120F/P Alternators always runs at synchronous speed and which is inversely proportional to no.of poles. so lesser the poles higher the speed and the minimum possible no. of poles is 2 for P=2,  Ns=3000 rpm for P=4, Ns=1500 rpm for P=6, Ns=1000 rpm for P=8, Ns=750 rpm The correct ans is P...

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To maximize any quantity we should differentiate that with respect to variable one and equate to zero,why?

To maximize any quantity we should differentiate that with respect to variable one and equate to zero,why? To obtain the maximum point for a function, we should differentiate it with respect to variable one and equate it to zero because once a quantity is at its maximum/minimum value there wont be any further change so the change (differentiation) is zero. For example, in dc motor to obtain the condition for maximum power developed by armature,the power equation is differentiated with respect to variable quantity Ia and equated to zero. (i.e)...

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A sine wave voltage source is connected across a series combination of a resistor and an inductor.The frequency is set so that inductive reactance is equal to resistance.If the frequency is increased then

A sine wave voltage source is connected across a series combination of a resistor and an inductor.The frequency is set so that inductive reactance is equal to resistance.If the frequency is increased then A.  Vr>Vl B.  Vr<Vl C.  Vl=Vr D.  none of the above Explanatory answer: XL=2*pi*f*L as f increases XL increases so voltage drop across inductor, IXL increases but voltage drop across resistance remains same because resistance not depends on frequency. The correct answer will be: Vr< ...

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A three- phase, three-stack variable reluctance stepper motor has 20 poles on each rotor and stator stack. The step angle of this motor is

A three- phase, three-stack variable reluctance stepper motor has 20 poles on each rotor and stator stack. The step angle of this motor is   (GATE-EE-2007) A. 3 B. 6 C. 9 D. 18 EXPLANATORY ANSWER: Step angle= 360/ m*Nr where Nr=no.of rotor poles m=no.of phases therefore   step angle=360/3*20 step angle...

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The slip of an induction motor normally does not depend on

The slip of an induction motor normally does not depend on  (GATE-EE-2012) A. Rotor speed B. Synchronous speed C. Shaft torque D. Core loss component EXPLANATORY  ANSWER : Slip= Ns-Nr / Ns So slip depends on both rotor speed(Nr) and synchronous speed (Ns) Torque varies as rotor speed (Nr) varies Hence the correct answer will be  Core loss compone...

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A 8 pole, DC generator has a simplex wave wound armature containing 32 coils of 6 turns each. It flux/pole is 0.06 wb.The machine is running at 250 rpm, calculate the induced armature voltage.

A 8 pole, DC generator has a simplex wave wound armature containing 32 coils of 6 turns each. It flux/pole is 0.06 wb.The machine is running at 250 rpm, calculate the induced armature voltage. (GATE-EE-2004)Given:P=8, DC gen,Wave(A=2),Coils C=32, turns per coil = 6, flux ø= 0.06 wb, speed N=250 rpmEMF E=?Solution:E=øZNP/60A , Turns T= coils * turns per coil =32*6= 192Z=2T= 2*192 = 384 conductorsE = 0.06*384*250*8 / 60*2Ans : E=384 volts ...

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The vector j5E is same as vector

The vector  j5E is same as vector A.   j2 E B . j E C.  J3 E D.  J4 E Explanatory answer : We know , j2=-1 and     j5=j2*j2*j j5= (-1) *(-1)* (j)= j therefore  j5 E can be written as  j E ...

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A 4 pole dynamo with wave wound armature has 51 slots containing 20 conductors in each slots.The induced emf is 357 volt and the speed is 8500 rpm . calculate the flux per pole. (GATE-EE-1996)

 A 4 pole dynamo with wave wound armature has 51 slots containing 20 conductors in each slots.The induced emf is 357 volt and the speed is 8500 rpm . calculate the flux per pole.  (GATE-EE-1996) Explanatory answer :  Given:  P=4 , Wave(A=2) , slots S= 51 , cond/slot = 20 , E= 357 volt  N = 8500 rpm , Ø = ? Sol:Total conductors = slots * cond/slot = 51 *20 = 1020 conductorsØ = E * 60 * A / ZNPØ = 357 * 60 * 2 / 1020 * 8500 * 4Ans: Ø = 1.23 m...

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Capacitive reactance is more when

Capacitive reactance is more when A. capacitance is less and frequency of supply is less B. capacitance is less and frequency of supply is more C. capacitance is more and frequency of supply is less D. capacitance is more and frequency of supply is more Explanatory answer: We know capacitive reactance reactance, Xc = 1 / 2ΠFC Xc is inversely proportional to F and C. Therefore Xc increases as frequency and capacitance decreases,hence the suitable answer is option ...

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The power consumed in a circuit element will be least when the phase difference between the current and voltage is

The power consumed in a circuit element will be least when the phase difference between the current and voltage is A. 180 B. 90 C. 60 D. 0 Explanatory answer: we know power in ac circuit,  P=VICOSø when  ø = 90, COS(90)= 0 Therefore the power consumed by the circuit will becomes zero at  ø = 90  (least value).  &nbs...

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ANNA UNIVERSITY UG/PG-2013 REVALUATION RESULTS

ANNA UNIVERSITY UG/PG-2013 REVALUATION RESULTS anna university ug/pg revaluation results has been announced, check it here... ANNA UNIVERSITY UG/PG REVALUATION RESULTS    (GRADE SYSTEMS) CLICK HERE ...

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Why silicon steel is preferred for magnetic core materials of electrical machines to reduce hysteresis losses ?

Explanatory answer : by steinmetz formula,                                Hysteresis loss,    Wh=n(Bmax)1.6f v watts Where n= hysteresis co-efficient f= frequency of reversal of magnetism v= volumeof magnetic material from the above above relation, we conclude that  hysteresis loss (Wh) is proportional to hysteresis co-efficient (n) hence by selecting a magnetic material with low hysteresis co-efficient value and high electrical resistivity...

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The peak value of a sine wave is 200V.Its average value is

The peak value of a sine wave is 200V.Its average value is  A. 127.4 V B. 141.4 V C. 282.8 V D. 200 V Ans: A Explanatory answer : For sinusoidal waveform, peak factor= peak value/ rms value =1.414 therefore  rms value = 200/ 1.414 = 141.44 and form factor = rms value/ average value = 1.11 therefore, average value = 141.44/ 1.11 = 127.4...

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A sine wave has a frequency of 50 HZ. Its angular frequency is............radian/second.

A sine wave has a frequency of 50 HZ. Its angular frequency is............radian/second. A. 100π  B. 50π   c. 25π   D. 5π    Ans:   A Explanatory answer : The relationship between frequency and angular velocity is                                     w=2πF  rad/sec where  w= angular velocity in rad/sec             F= frequency in HZ Therefore...

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An ammeter has a current range of 0 - 5 A, and its internal resistance is 0.2Ω . In order to change the range to 0 - 25 A, we need to add a resistance of

An ammeter has a current range of 0 - 5 A, and its internal resistance is 0.2Ω . In order to change the range to 0 - 25 A, we need to add a resistance of                    (GATE-EE-2010) (A) 0.8Ω in series with the meter (B) 1.0Ω in series with the meter (C) 0.04Ω in parallel with the meter  (D) 0.05Ω in parallel with the meter Ans: D Explanatory answer : In ammeter designs, external...

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A bulb in a stair case has two switches, one switch being at ground floor and other one at first floor. The bulb can be turned on and also can be turned off by any one of the switches irrespective of the state of other switch.The logic of switching of bulb resembles

A bulb in a stair case has two switches, one switch being at ground floor and other one at first floor. The bulb can be turned on and also can be turned off by any one of the switches irrespective of the state of other switch.The logic of switching of bulb resembles (GATE-EC-2013) (a) an AND gate (b) an OR gate (c) an XOR gate (d) an NAND gate ANS: C EXPLANATORY ANSWER: The purpose of staircase wiring is, one should be able to switch on...

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ANNA UNIVERSITY INTERNAL ASSESMENT AND ATTEDANCE DETAILS FOR NOV/DEC2013&JAN 2014

Anna university internal and attendance report,NOV/DEC-2013 Anna university instructed to all colleges to enter their Attendance Details and Assessment Marks in the COE Web Portal  from  the academic year 2013 onwards.  How to check  attendance report and internal mark : 1. click here 2.go to student log in, enter your registration number, date of birth & verification then click log in 3.Click assesment details tab to check your attendance report and internal mark...

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A practical current source is usually represented by

 A practical current source is usually represented by                                                         (GATE-EE-1997)  A.a resistance in series with a ideal current source   B.a resistance in parallel with a ideal current source   C.a resistance in parallel...

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WALK-IN INTERVIEW” FOR GRADUATES IN ENGINEERING FOR APPRENTICESHIP TRAINING ON 16th Sep, 2013 at BEL PANCHKULA

GRADUATE APPRENTICES Eligibility : BE/B.Tech(CSE, EEE, ECE, IT, Mech) Location : Haryana-other Last Date : 16 Sep 2013 Mode of Selection: Selection will be through interview only. Age limit:  25 years as on 01 .10 .2013.  Stipend : Rs.3560 Qualification: Candidates should have passed Degree examination on or after 01. 01. 2012.  Documents to be produced at the time of Interview:  1. SSLC Marks Sheet (as proof of age)- Original with one attested photocopy. 2. Original Degree Certificate...

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GATE-EE-2014-SYLLABUS

GATE 2014 Syllabus for Electrical Engineering (EE) ENGINEERING MATHEMATICS Linear Algebra: Matrix Algebra, Systems of linear equations, Eigen values and eigen vectors. Calculus: Mean value theorems, Theorems of integral calculus, Evaluation of definite and improper integrals, Partial Derivatives, Maxima and minima, Multiple integrals, Fourier series. Vector identities, Directional derivatives, Line, Surface and Volume integrals, Stokes,...

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