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ENGINEERS INSTITUTE OF INDIA® 1 ELECTRICAL ENGINEERING 1. 2. 3. 4. 5. A single phase transformer is connected to a supply of voltage V and frequency f and is supplying a load, connected across its secondary winding. If the supply voltage is reduced from V to V/2, the flux established in the core will (a.) decrease by nearly 50% (b.) increase by nearly 50% (c.) remain unchanged (d.) be affected by amount of load and not by the applied voltage Under magnetic saturation of the core of a transformer, the reactance parameters of its equivalent circuit are affected such that (a.) X1 and X2 increase while Xm does not change (b.) X1 and X2 do not change while Xm decreases (c.) X1 and X2 do not change while Xm increases (d.) X1 and X2 decreases while Xm does not change A single phase 2000/200 V, 10 kVA, two winding transformer is reconnected as a stepup autotransformer with 2000 V winding as primary. The kVA rating of the autotransformer shall be (a.) 10 kVA (b.) 11 kVA (c.) 110 kVA (d.) 220 kVA The power factor at which power is drawn by a transformer is (a.) very low under O.C. test but high under S.C. test (b.) high under O.C. test but low under S.C. test (c.) low both under O.C. and S.C. tests (d.) high both under O.C. and S.C. tests The O.C.C. of a shunt d.c. generator is represented by E = 12+66I. If the field resistance is 70 ohms, the no-load voltage of the generator will be (a.) 144 V 6. 7. 8. 9. (b.) 210 V (c.) 220 V (d.) 288 V In d.c. shunt motors, the developed torque is proportional to (a.) induced e.m.f. (b.) armature current (c.) output power (d.) line current The speed of a separately excited d.c. motor can be controlled below base speed by (a) armature resistance control and (b) supply voltage control. What happens to the slope of modified speed-torque characteristics under the two methods? (a.) It changes in both types of control (b.) It remains unchanged in both types of control (c.) It remains unchanged in armature resistance control while changes in supply voltage control (d.) It remains unchanged in supply voltage control while changes in armature resistance control The polarity of interpoles used in d.c. machines is (a.) same as the main pole ahead in generators while opposite of the main pole ahead in motors (b.) same as the main pole ahead ion motors while opposite of the main pole ahead in generators (c.) same as the main pole ahead in both motors and generators (d.) opposite of the main pole ahead in both motors and generators In synchronous generators, examine the following statements about voltage regulation: 1. Synchronous impedance method gives pessimistic results 2. MMF method gives optimistic results 28-B/7, Jia Sarai, Near IIT, Hauz Khas, New Delhi-110016. Ph. 09990657855, 011-26514888. www.engineersinstitute.com 10. 11. 12. 13. 14. ENGINEERS INSTITUTE OF INDIA® 2 3. In unsaturated machine both methods (d.) 14.0 (synchronous impedance and MMF) 15. An electric motor developing a starting give same results. torque of 10 Nm starts with a load of 6 Nm at Which of the statements are correct? its shaft. If the acceleration at start is 2 (a.) 1, 2 and 3 rad/sec2 , the moment of inertia of the system (b.) Only 1 and 2 must be (c.) Only 3 (a.) 2 kg-m2 (d.) Only 2 and 3 (b.) 2 N-m2 Under symmetrical short circuit of a (c.) 0.5 kg-m2 synchronous generator, the armature reaction (d.) 0.5 N-m2 is 16. A synchronous motor works as a synchronous (a.) magnetizing condenser if (b.) demagnetizing (a.) underexcited (c.) cross-magnetising (b.) overexcited (d.) mainly magnetising (c.) excited with 100% excitation In synchronous generators, the fifth harmonic (d.) unexcited in induced emf can be eliminated by using 17. In relation to damper bar winding in a coils show chorded by an angle synchronous motor, examine the following o (a.) 9 statements: (b.) 18o 1. Damper bars are provided in slots on o (c.) 27 poles o (d.) 36 2. Damper bars improve excitation In induction motor operation, a slip greater 3. Damper bars help the motor self start than 1 refers to 4. Damper bars minimize hunting. (a.) regenerative braking Which of the statements are correct? (b.) motoring in reverse direction (a.) 1, 2, 3 (c.) plugging (b.) 2, 3 (d.) dynamic braking (c.) 1, 4 As the applied voltage to an induction motor, (d.) 1, 3, 4 operating under no-load, is reduced to half 18. In large power ratings, synchronous motor is (a.) its speed reduced and stator current considered superior to induction motor, since increases (a.) it is less expensive (b.) its speed reduced and stator current also (b.) its efficiency is better reduces (c.) it can be operated at better power factor (c.) its speed reduces but there is not change (d.) its speed regulation is superior. in stator current 19. An induction motor drive is designed for two (d.) there is no change in speed but stator speed operation. For this purpose, the motor current reduces is provided with two windings on its stator A 3-phase induction motor is delivering a corresponding to 4 poles and 8 poles. While load of 10 kW at a lagging p.f. of 0.5. If a 3the motor was running on 4 pole winding, a phase capacitor bank of 7.3 kVAR is changeover to 8 pole winding is made. The connected at its input, the resulting kVA motor will drawn from supply shall be (approximately) (a.) experience dynamic braking (a.) 26.5 (b.) experience regenerative braking (b.) 24.5 (c.) experience no braking but will slow (c.) 20.0 down due to its inertia 28-B/7, Jia Sarai, Near IIT, Hauz Khas, New Delhi-110016. Ph. 09990657855, 011-26514888. www.engineersinstitute.com 20. 21. 22. 23. ENGINEERS INSTITUTE OF INDIA® 3 (d.) draw dangerously high current 24. In a 3-phase full controlled thyristor bridge A d.c. shunt motor drive of 100 h.p. is run (a) rectifier operating under continuous at half the rated speed by armature voltage conduction mode, each thyristor conducts for control and (b) at 1.5 times the rated speed by (a.) 180o and two thyristors conduct at a time field control. Its power rating in the two cases (b.) 120o and three thyristors conduct at a shall be modified as time (a.) 100 h.p. in both cases (c.) 180o and three thyristors conduct at a (b.) 50 h.p. in case (a) and 150 h.p. in case time (b) (d.) 120o and two thyristors conduct at a time (c.) 50 h.p. in case (a) and 100 h.p. in case 25. A single phase fully controlled rectifier is (b) feeding a d.c. motor. At = 0o, the armature (d.) 100 h.p. in case (a) and 150 h.p. in case voltage is 200 V and motor speed is 1000 (b) rpm. Neglecting armature resistance and A single phase full controlled rectifier can considering continuous conduction, the work as inverter, if the firing angle is between armature voltage and speed at = 60o will be o o (a.) 0 and 90 (a.) 100 V and 500 rpm o o (b.) 60 and 90 (b.) 100 V and 1000 rpm (c.) 90o and 180o (c.) 200 V and 500 rpm (d.) 0o and 60o (d.) 100 V and speed will depend upon load When d.c. voltage is converted to a.c. by an 26. The grading capacitors are provided across inverter, PWM technique is used to the series connected interrupters in EHV (a.) control only the output voltage from circuit breakers for within the inverter (a.) reducing short circuit current (b.) control both the output voltage and (b.) improving power factor frequency from within the inverter (c.) equalizing distribution of recovery (c.) control the output current voltage across the interrupters (d.) reduce losses in the inverter (d.) preventing inductive current chopping. A thyristor which is in ON state is to be 27. The minimum cost operating condition for a switched OFF. For this purpose a reverse bias thermal plant is that is applied across it. Examine the following (a.) the larger units should generate more statements regarding flow of current from power as compared to smaller units anode to cathode (forward current): (b.) the smaller units should generate more 1. Forward current can continue to flow if power as compared to larger units the circuit is purely resistive (c.) the incremental cost rate of the units be 2. Forward current can continue to flow if proportional to their rating the circuit is dominantly inductive (d.) the incremental cost rate of all the units 3. Forward current can continue to flow if be equal the circuit is dominantly capacitive 28. The effect of earth on a three-phase 4. Forward current will immediately stop transmission line is to flowing. (a.) increase its capacitance and decrease Which of the above statements are correct? inductance (a.) Only 4 (b.) decrease its capacitance and increase (b.) Only 1 inductance (c.) Only 2 and 3 (c.) increase its capacitance without affecting (d.) Only 2 inductance 28-B/7, Jia Sarai, Near IIT, Hauz Khas, New Delhi-110016. Ph. 09990657855, 011-26514888. www.engineersinstitute.com 29. 30. 31. 32. ENGINEERS INSTITUTE OF INDIA® 4 (d.) increase its inductance without affecting (a.) the diversity factor and load factor both capacitance. should be low In case of a transmission line if the voltage (b.) the diversity factor and load factor both regulation is negative, then the load power should be high factor is (c.) the diversity factor should be high while (a.) zero the load factor should be low (b.) lagging (d.) the diversity factor should be low and (c.) unity the load factor should be high (d.) leading 35. The coefficients of reflection for voltage and The voltage gradient at the surface of a cable, current for an open ended line are having a conductor of radius r and a sheath of respectively radius R, is minimum when (a.) -1.0 and -1.0 (a.) R = r/e (b.) -1.0 and 1.0 (b.) R = r (c.) 1.0 and 1.0 (c.) R =er (d.) 1.0 and -1.0 r (d.) R = e 36. If G is the MVA rating of a synchronous where e = natural exponent machine with inertia constant H sec. and In an N-bus power system with M-PV buses, operating frequency f, then the angular the size of the Jacobian matrix for load flow momentum M of the machine, in MJcalculation is sec/electrical degree, is (a.) N×N GH (a.) (b.) (N-M) ×(N-M) 180 f (c.) (N-1) × (N-1) GH (d.) (N-M-1) × (N-M-1) (b.) 360 f The zero-sequence equivalent circuit of a GH delta-star transformer, with solidly grounded (c.) neutral, is f (a.) (b.) (c.) (d.) 33. The plug setting multiplier of a 5 Amp. IDMT relay for a fault current of 4000 Amp. and a relay setting of 125%, with a C.T. ratio of 80 will be (a.) 1 (b.) 2 (c.) 4 (d.) 8 34. If the cost of electricity generation is to be reduced then (d.) H 180 f 37. Circular grooves are provided underneath the insulator disc for (a.) reducing the weight of the disc (b.) improving disc strength (c.) increasing cooling of the disc (d.) increasing the creepage distance 38. The arc formation in vacuum circuit breaker is initiated by (a.) field emission (b.) thermal emission (c.) photo emission (d.) secondary emission 39. The series reactors are used to (a.) limit over voltages (b.) control Ferranti effect (c.) limit fault current (d.) improve stability 28-B/7, Jia Sarai, Near IIT, Hauz Khas, New Delhi-110016. Ph. 09990657855, 011-26514888. www.engineersinstitute.com 40. 41. 42. 43. ENGINEERS INSTITUTE OF INDIA® 5 If the spacings Dab, Dbc and Dca between the that Area Control Error (ACE) must be zero phases a, b, and c of a three phase at least once in a transmission line are not equal, then the (a.) 1 sec period equivalent spacing Deq can be calculated as (b.) 1 min period (a.) (Dab + Dbc + Dca)/3 (c.) 10 min period (b.) (Dab * Dbc * Dca)/3 (d.) 1 hr period (c.) (Dab + Dbc + Dca)1/3 46. If a network has b branches and n nodes, then (d.) (Dab * Dbc * Dca)1/3 the number of independent KVL equations For calculating fault current for a double line for the network are to ground fault in an ungrounded system (a.) b-n (a.) positive, negative and zero sequence (b.) n-b+1 networks are connected in series (c.) b-n-1 (b.) positive, negative and zero sequence (d.) b-n+1 networks are connected in parallel 47. What will be the value of ZL for maximum (c.) positive and negative sequence networks power transfer condition in the circuit shown are connected in parallel in Fig. Q.47? (d.) positive and negative sequence networks are connected in series The unit of R, the regulation constant of turbine speed governor, is (a.) Hz/MW (b.) MW/sec (a.) (2-j2) (c.) MW/Hz (b.) (2+j2) (d.) MW-Hz (c.) (3-j2) If in a power system the line to line base (d.) (3+j2) voltage is VB kV and the 3-phase base MVA 48. Which of the following statements does not is SB, then the base impedance of the system apply to series RLC circuit? is (a.) The current and the admittance are VB2 maximum at resonance (a.) 3S B (b.) The phase angle of the impedance changes from +90o to –90o as the 3VB2 (b.) frequency is varied from 0 to SB (c.) The total stored energy in the circuit is V2 constant at resonance (c.) B SB (d.) The power factor is unity at resonance 49. The average value of a sine wave over a full 2 V *1000 (d.) B cycle is SB 44. The pumped storage hydro plants are used as (a.) Base load plants (b.) Peak load plants (c.) Mid-range plants (d.) both (A) and (B) 45. The specified operating criteria for the proper operation of interconnected power system is , 2Vmax V (b.) max 2 V (c.) max (a.) (d.) zero 28-B/7, Jia Sarai, Near IIT, Hauz Khas, New Delhi-110016. Ph. 09990657855, 011-26514888. www.engineersinstitute.com 50. 51. 52. 53. 54. 55. ENGINEERS INSTITUTE OF INDIA® 6 A two port network is reciprocal and symmetrical, if ABCD parameters satisfy the conditions: (a.) AB-CD = 1 and A = D (b.) AD-BC = 1 and A = D (a.) Networks A and B are coupled (c.) AC-BD = 1 and A = D (b.) A is an active network (d.) AD-BC = 1 and B = C (c.) B is a passive network Tellegen’s theorem is applicable to (d.) B is a non-linear network (a.) linear time invariant networks only 56. If XY= 0 then XY is equal to (b.) non-linear time invariant network only (a.) X+Y (c.) any network satisfying Kirchoff’s (b.) X+Y current and voltage laws (d.) linear time variant network only (c.) X Y+X Y The circuit element having identical (d.) 1 properties for forward and reverse direction 57. The value of base x will be of current flow through it, is called a (101)x + (110)7 = (101)8 + (29)16 (a.) linear element (a.) 2 (b.) irreversible element (b.) 7 (c.) bilateral element (c.) 8 (d.) unilateral element (d.) 10 A fundamental cut set contains 58. Consider the counter circuit shown in Fig. (a.) only one tree branch and minimum Q.58. number of links (b.) only one link and minimum number of tree branches (c.) only tree branches (d.) only links In the circuit shown in Fig. Q. 54 if the switch is opened at t = 0 and the initial current through the switch and L1 is 10 A, then the current i(t) and the voltage v(t) of t > If the present state QA QB of the counter is QA 0 are = 1 & QB = 0, the next state of the counter will be (a.) QA = 1, QB = 1 (b.) QA = 1, QB = 0 (c.) QA = 0, QB = 1 (d.) QA = 0, QB = 0 59. In 8085 A p, stack pointer is a 16 bit register which is (a.) 0 A, 0 V (a.) Incremented by 2 whenever data is (b.) 0 A, V pushed on to stack (c.) 6 A, 12 V (b.) Incremented by 2 whenever data is (d.) 10 A, 20 V popped from stack The Thevenin and Norton equivalents of (c.) Incremented by 1 whenever data is network A at points X, Y (Fig. Q.55) can not pushed on the stack be found if 28-B/7, Jia Sarai, Near IIT, Hauz Khas, New Delhi-110016. Ph. 09990657855, 011-26514888. www.engineersinstitute.com ENGINEERS INSTITUTE OF INDIA® 7 (d.) Neither incremented nor decremented a result of PUSH and POP operation 60. The instruction LDA 0805H is used to input a (a.) Zener diode data from an I/O device. Choose the correct (b.) Esaki diode statement (c.) Varistor (a.) It is possible only if device is interfaced (d.) Varactor using memory mapped I/O 66. The V-I characteristic shown in Fig. Q. 66 is (b.) It is possible only if device is interfaced that of using I/O mapped I/O (c.) Instead of LDA 0805H, the instruction STA 0805H should be used (d.) only IN PORT instruction can be used in 8085 A p. 61. The macro RTL implemented by INR M in 8085 A microprocessor is (a.) PN junction diode (a.) (M) (M) +1 (b.) Tunnel diode (b.) (H,L)(H,L) + 1 (c.) Zener diode (c.) M(H,L) M(H,L) +1 (d.) Varactor (d.) (H) (H) + 1, (L) (L) +1 67. In a four variable V-K Map shown in Fig. 62. In an 8085 A microprocessor when INTR simplified expression for X is interrupt, becomes active, the control will be transferred to (a.) 0024 H memory location (b.) 003C H memory location (c.) anywhere in the memory decided by the interrupting device (d.) 0034 H memory location 63. In an 8255 programmable peripheral interface both the groups are programmed in made ‘0’. The possible number of combination in which the ports can be programmed is (a.) 16 (b.) 4 (c.) 3 (d.) 2 64. The meaning of direct addressing mode is (a.) The address of operand is available in register pair (b.) The address of operand is available in PC (c.) The data is directly available in the instruction itself (d.) The address of the operand is available in the instruction itself. 65. The schematic symbol shown in following Fig. Q. 65 is that of (a.) AB+ CD (b.) A B + C D (c.) B D (d.) A D + B C 68. In following circuit assuming voltage drop of LED as 2 V, the LED current when transistor is saturated will be (a.) 12 mA (b.) 9.7 mA (c.) 6 mA (d.) 5.8 mA 69. In the following circuit the collector voltage VC is (assume VBE = 0.7 V) 28-B/7, Jia Sarai, Near IIT, Hauz Khas, New Delhi-110016. Ph. 09990657855, 011-26514888. www.engineersinstitute.com 70. 71. 72. 73. ENGINEERS INSTITUTE OF INDIA® 8 (d.) 1.4 % 74. The coil of an instrument has 40 turns. The mean length of the coil is 25 mm and the axial length of the coil is 20 mm. If the flux density is 0.1 T and the coil current is 20 mA, the torque on the moving coil will be (a.) 40×10–6 N-m (b.) 20×10–6 N-m (c.) 40×10–3 N-m (d.) 20×10–3 N-m 75. In thermocouple element, heat energy (a.) -17.4 V transferred to the hot junction is converted to (b.) 5.6 V electrical energy by (c.) 12.3 V (a.) Johnson’s effect (d.) 17.4 V (b.) Seebeck effect From the following V-K map the simplified (c.) Hall effect expression for Z is (d.) Faraday’s effect 76. The scale of dynamometer type instrument marked in terms of RMS value would be (a.) uniform throughout (b.) non-uniform, crowded near full scale (c.) non-uniform, crowded at the beginning (d.) non-uniform, crowded around mid-scale (a.) ABC ABC 77. The harmonic distortion percentage is (b.) ABC ABC accurately measure with (c.) B (a.) V.T.V.M. (d.) ABC ABC ABC ABC (b.) An oscilloscope The method of absolute measurement of (c.) Harmonic distortion meter resistance is (d.) Square wave generator (a.) Ohm method 78. A thermometer has a time constant of 3.5 s. It (b.) Potentiometer method is quickly taken from a temperature 0oC to (c.) Lorenz method water bath at 100oC. What temperature will (d.) Rayleigh method be indicated after 1.5 s? The instrument which gives the value of the (a.) 100oC quantity to be measured in terms of (b.) 50oC instrument constants and its deflection is (c.) 35oC called the (d.) 15oC (a.) absolute instrument 79. A digital voltmeter employees an ADC which (b.) secondary instrument requires a start pulse, uses an analog (c.) recording instrument comparator and has a relatively fixed (d.) integrating instrument conversion time independent of applied The current passing through a resistor of voltage. The ADC is (500.2) is (4.00.02)A. The limiting error (a.) digital ramp converter in the computed value of power will be (b.) dual slope converter (a.) 0.2 % (c.) successive approximation converter (b.) 0.4 % (d.) flash type (c.) 0.9 % 28-B/7, Jia Sarai, Near IIT, Hauz Khas, New Delhi-110016. Ph. 09990657855, 011-26514888. www.engineersinstitute.com 80. 81. 82. 83. 84. 85. 86. ENGINEERS INSTITUTE OF INDIA® 9 In measurements made using Q-meter, 2. Gain margin and phase margin are impedance elements should be connected in positive (a.) star 3. All roots of characteristic equation must (b.) delta lie in left half of s-plane (c.) series 4. Gain margin is positive and phase (d.) parallel margin is negative The measured values of iron losses of a Out of these statements magnetic specimen are 15 W and 25 W at, 40 (a.) 1 and 3 are correct Hz and 60 Hz respectively at constant flux (b.) 1 and 2 correct density. The respective hysteresis and eddy (c.) 2 and 3 are correct current losses at 50 Hz are (d.) 3 and 4 are correct (a.) 14.584 W and 5.208 W 87. In the feedback system shown below, if the (b.) 7.5 W and 12.5 W steady state error for a step input is 0.05, then (c.) 5.208 W and 14.548 W the value of K is (d.) 5 W and 10 W The most common and best bridge method for precise measurement of inductance over a wise range is (a.) Maxwell’s (a.) 0.05 (b.) Hay’s (b.) 0.95 (c.) Wien (c.) 1.9 (d.) Anderson (d.) 19 The AC bridge that can be used for accurate 88. Match List I with List II and select the correct determination of excitation frequency is answer using the codes given below the lists: (a.) Wien bridge List I (Location of poles on s-plane) (b.) Schering bridge (c.) Anderson bridge (d.) De Sauty bridge A thermo-couple arrangement is to be used to A. measure temperature in the range of 700800oC. Point out the pair that would be most suitable for this application B. (a.) Copper-constantan (b.) Chromel-alumel (c.) Platinum-platinum rhodium C. (d.) Iron-constantan Rotameter is employed for measuring (a.) flow D. (b.) rotation List II (Impulse Response) (c.) specific gravity (d.) viscosity Consider the following statements regarding the stability of a control system 1. 1. Gain margin and phase margin are negative 28-B/7, Jia Sarai, Near IIT, Hauz Khas, New Delhi-110016. Ph. 09990657855, 011-26514888. www.engineersinstitute.com ENGINEERS INSTITUTE OF INDIA® 10 2. (d.) 90. A unity feedback second order control system 3. 4. Codes: A B C D (a.) 4 1 2 3 (b.) 3 4 2 1 (c.) 1 3 2 4 (d.) 1 3 4 2 89. The Nyquist plot for a control system is shown in Fig. Q.89. The Bode plot of |G| for the same system will be (a.) (b.) (c.) is characterized by G s K s Js B where J = moment of inertia B = viscous damping coefficient K = system gain The transient response specification which is not affected by variation of system gain is the (a.) peak overshoot (b.) damped frequency of oscillations (c.) setting time (d.) rise time 91. The second order system X = AX has 1 1 A . The value of its damping 1 0 factor and natural frequency n are respectively (a.) 0.5 and 1 (b.) 1 and 1 (c.) 0.707 and 2 (d.) 1 and 2 92. A negative unit feedback system has forward path transfer function as Ks/(s2+2s+25). The break in point(s) of root locus occur at (a.) s=5 (b.) s=-5 (c.) both A & B (d.) s = 25 93. In an electrical analog of mechanical system of rotational motion, using torque-voltage analogy, inertial and viscous damper are respectively analogous to (a.) Inductance and capacitance (b.) Capacitance and resistance (c.) Inductance and resistance (d.) Capacitance and inductance 94. The characteristic equation of a feedback system is given by 28-B/7, Jia Sarai, Near IIT, Hauz Khas, New Delhi-110016. Ph. 09990657855, 011-26514888. www.engineersinstitute.com ENGINEERS INSTITUTE OF INDIA® 11 The condition for complete state K s 4 6s 3 11s 2 6s 0 controllability and complete observability is 4 (a.) d1 > 0, b2 > 0, b1 and d2 can be anything For this system, stable closed loop behavior (b.) d1 > 0, d2 > 0, b1 and b2 can be anything can be ensured when gain K is such that (c.) b1 > 0, b2 > 0, d1 and d2 can be anything (a.) 0 K 40 (d.) b1 > 0, b2 > 0, d1 < 0 and d2 can be (b.) 0 K 10 anything (c.) 0 K 99. The semilog plot of gain characteristic (d.) 0 K 20 (BODE plot) of a network is shown in the a 1 Fig. Q.99. 95. The eigen values of the matrix are a 1 (a.) (a+1), 0 (b.) a, 0 (c.) (a-1), (a-1) (d.) 0, 0 96. A first order linear system is initially relaxed. For a unit step signal u(t), the response of the system is (1-e-3t), t > 0 If a signal 3. u(t) + (t) is applied to the same initially relaxed system, the response will be (a.) 3(1-e-3t) .u(t)+ e-3t. (t) (b.) (1-3e-3t) .u(t) (c.) 3(1+e-3t) .u(t) (d.) 3.u(t) 97. Consider the following statements regarding the non linear system 1. dead zone can be classified as single valued non-linearity 2. hysteresis and backlash can be classified as double valued non-linearity 3. Coulomb friction can be classified as double valued non-linearity Out of these statements (a.) 1 and 3 are correct (b.) all three are correct (c.) 1 and 2 are correct (d.) 2 and 3 are correct 98. Consider the system The gain cross over frequency c is (a.) 20 rad/sec (b.) 30 rad/sec (c.) 40 rad/sec (d.) 25 rad/sec 100. The pole-zero configuration of a phase lead compensating network is given by (a.) (b.) (c.) b 1 1 X t X t 1 U (t ) 0 1 b2 C t [d1 d2 ] X (t ) . (d.) 28-B/7, Jia Sarai, Near IIT, Hauz Khas, New Delhi-110016. Ph. 09990657855, 011-26514888. www.engineersinstitute.com