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August 14th, 2014, 04:17 PM
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Please provide me question paper for BSNL Telecom Technical Assistants (TTA) examination ? Here I am giving you question paper for BSNL Telecom Technical Assistants (TTA) examination...... 1. One of the following statement which is true for relative dielectric constant is - a) It is dimensionless b) It is not equal to unity for vacuum c)) It?s value for all substances is less than one d)) None 2. Pure metals generally have- a) high conductivity and low temperature coefficient b) high conductivity and large temperature coefficient c) low conductivity and zero temperature coefficient d) low conductivity and high temperature coefficient 3. For small size, high frequency coils, the most common core material is a) Air b) Ferrite c) Powdered ion d) Steel 4. For an abrupt junction Varactor diode, the dependence of device capacitance (C) on applied reverse bias (V) is given by- a) C a V1/3 b) C a V-1/3 c) C a V1/2 d) C a V-1/2 5. A superconductor is a- a) A material showing perfect conductivity and Meissner effect below a critical temperature b) A conductor having zero resistance c) A perfect conductor with highest dimagnetic susceptibility d) A perfect conductor which becomes resistive when the current density through it exceeds a critical value 6. When a semiconductor based temperature transducer has a temperature coefficient of ?2500 mV/0C then this transducer is indeed a- a) Thermistor b) Forward biased pn junction diode c) Reverse biased pn junction diode d) FET 7. The location of lightning arrestor is - a) Near the transformer b) Near the circuit breaker c) Away from the transformer d) None 8. Time constant of an RC circuit increases if the value of the resistance is - a) Increased b) Decreased c) Neither a nor b d) Both a and b 9. Intrinsic semiconductors are those which - a) Are available locally b) Are made of the semiconductor material in its purest from c) Have more electrons than holes d) Have zero energy gaps 10. The primary control on drain current in a JFET is exerted by - a) Channel resistance b) Size of depletion regions c) Voltage drop across channel d) Gate reverse bias 11. The electrical conductivity of metals which is expressed in ohm-1 m-1 is of the order of - a) 1010 b) 105 c) 10-4 d) 10-6 12. When biased correctly, a zener diode ? a) acts as a fixed resistance b) has a constant voltage across it c) has a constant current passing through it d) never overheats 13. The current amplification factor adc is given by ? a) IC/IE b) IC/IB c) IB/IC d) IB/IC 14. Compared to bipolars, FETs have- a) high input impedance b) low input impedance c) same input impedance d) none 15. The source-drain channel of JFET is - a) ohmic b) bilateral c) unilateral d) both a and b 16. diac is equivalent to a - a) Pair of SCRs b) Pair of four layer SCRs c) Diode and two resistors d) Triac width 17. When a sample of N type semiconductor has electron density of 6.25 ? 1011 /cm3 at 300K and if the intrinsic concentration of carriers in this sample is 2.5 ? 1013/cm3 then the hole density will be ? a) 106/cm3 b) 103/ cm3 c) 1010/ cm3 d) 1012/ cm3 18. The statement ‘In any network of linear impedances, the current flowing at any point is equal to the algebraic sum of the currents caused to flow at that point by each of the sources of emf taken separately with all other emf’s reduced to zero? represents - a) Kirchhoff’s law b) Norton’s theorem c) Thevenin’s theorem d) Superposition theorem 19. One of the following modes which has the characteristics of attenuation becoming less as the frequency is increased and is attractive at icrowave frequencies of circular cylindrical wave guides is ? a) TE1 mode b) TM01 mode c) TE01 mode d) Higher order mode 20. A two-port network is symmetrical if ? a) z11z22 ? z12z21 = 1 b) h11h22 ? h12h21 = 1 c) AD ? BC = 1 d) y11y22 ? y12y21 = 1 21. For transmission line load matching over a range of frequencies, it is best to use a- a) balun b) broad band directional coupler c) double stub d) single stub of adjustable position 22. The poles and zeros of a driving point function of a network are simple and interlace on the negative real axis with a pole closest to the origin. It can be realised - a) by an LC network b) as an RC driving point impedance c) as an RC driving point admittance d) only by an RLC network 23. Poles and zeros of a driving point function of a network are simple and interlace on the jw axis. The network consists of elements ? a) R and C b) L and C c) R and L d) R, L and C 24. For a two port reciprocal network, the output open circuit voltage divided by the input current is equal to ? a) B b) Z12 d) h12 25. In a short electric doublet the radiation properties are so that- a) The induction field diminishes as the square root of the distance and is only appreciable in the vicinity of the conductor. b) In the radiation, magnetic field is minimum when the current is maximum. c) The radiation resistance of a short doublet antenna is extremely high. d) Mean rate of power through a unit area of spherical sphere surrounding this doublet is proportional to the square of the elemental length, other factors remaining constant. 26. The frequency modulated (FM) radio frequency range is nearly - a) 250 ?300 MHz b) 150 ? 200 MHz c) 90 ? 105 MHz d) 30-70 MHz 27. In an underground cable the distortion in the transmission of carrier frequency can be eliminated by using - a) Inductive loading b) Resistive loading c) Capacitive loading d) Shielding 28. The charachteristic impendance of a transmission line with inductance 0.294 mH /m and capacitance 60 pF/m is - a) 49 W b) 60 W c) 70 W d) 140 W 30. For a quarter wavelength ideal transmission line of characteristic impedance 50 ohms and load impedance 100 ohms, the input impedance will be ? a) 25W b) 50W c) 100W d) 150W 31. The depth of penetration or skin depth for an electromagnetic field of frequency ?f? in a conductor of resistivity r and permeability m is- a) inversely proportional to r and f and directly proportional to m b) directly proportional to r and inversely proportional to f and m c) directly proportional to f and inversely proportional to r and m d) inversely proportional to r and m and directly proportional to f 32. When an antenna has a gain of 44dB then assuming that the main beam of the antenna is circular in cross-section the beam width will be - a) 0.4456 0 b) 1.44560 c) 2.44560 d) 3.44560 33. Lens antennas used for microwaves are usually made of - a) Polystyrene b) Glass of low refractive index c) Paraboloid surfaces d) Dielectric media having large refractive index 34. One of the following types of instrument which is an electrometer is - a) Electrodynamometer b) PMMC c) Electrostatic d) Moving iron 35. When an ac current of 5A and dc current of 5A flow simultaneously through a circuit then which of the following statement is true ? a) An ac ammeter will read less than 10A but more than 5A b) An ac ammeter will read only 5A c) A dc ammeter will read 10A d) A dc ammeter will read zero 36. When Q factor of a circuit is high, then - a) power factor of the circuit is high b) impedance of the circuit is high c) bandwidth is large d) none of these 37. The resolution of a logic analyser is - a) the maximum number of input channels b) the minimum duration of the glitch it can capture c) it’s internal clock period d) the minimum amplitude of input signal it can display 38. A memoryless system is ? a) causal b) not causal c) nothing can be said d) none 39. An air capacitor is a ? a) time variant b) active device c) time invariant d) time invariant and passive device 40. Thermistors are made of - a) pure metals b) pure insulators c) sintered mixtures of metallic oxides d) pure semiconductor 41. Pirani gauge is used to measure ? a) very low pressures b) high pressures c) pressures in the region of 1 atm d) fluid flow 42. These circuits converts input power at one frequency to output power at a different frequency through one stage conversion ? a) AC voltage controllers b) Cyclo converters c) Phase controlled rectifiers d) Inverters 43. In a forward voltage Triggering thyristor changes from ? a) off state to on state b) on state to off state c) on state to on state d) off state to off state 44. A thyristor, when triggered, will change from forward blocking state to conduction state if its anode to cathode voltage is equal to - a) peak repetitive off state forward voltage b) peak working off state forward voltage c) peak working off state reverse voltage d) peak non-repetitive off state forward voltage 45. Gate characteristic of a thyristor- a) is a straight line passing through origin b) is of the type Vg = a + bIg c) is a curve between Vg and Ig d) has a spread between two curves of Vg ? Ig 46. A four quadrant operation requires- a) two full converters in series b) two full converters connected back to back c) two full converters connected in parallel d) two semi converters connected back to back 47. If for a single phase half bridge inverter, the amplitude of output voltage is Vs and the output power is P, then their corresponding values for a single phase full bridge inverter are ? a) Vs, P b) Vs/2, P c) 2Vs, 2P d) 2Vs, P 48. In an enhancement type MOSFET the output V-I characteristics has ? a) only an ohmic region b) only a saturation region c) only ohmic region at 10 W voltage value followed by a saturation region at higher voltages d)an ohmic region at large voltage values preceded by a saturation region at lower voltages 49. The energy gap in a semiconductor - a) increases with temperature b) remains constant c) slightly increase with temperature d) decrease with temperature 50. In an electronic circuit matching means - a) connecting a high impedance directly to low impedance b) selection of components which are compatible c) transferring maximum amount of signal between different kinds of circuits. d) RC coupled stages 51. P channel FETs are less superior than N channel FETs because a) They have higher input impedance b) They have high switching time c) They consume less power d) Mobility of electrons is greater than that of holes 52. Small increase in temperature in the CE connected transistor is the - a) Increase in ICEO b) Increase in ac current gain c) Decrease in ac current gain d) Increase in output resistance 53. An amplifier has a band width of 20 KHz and a midband gain of 50 without feedback. If a negative feedback of 1% is applied then bandwidth with feedback is - a) 13. 3 KHz b) 30KHz c) 10KHz d) 40KHz 54. The output of a class B amplifier - a) is distortion free b) consists of positive half cycles only c) is like the output of a full wave rectifier d) comprises short duration current pulses 55. An amplifier with negative feedback - a) lowers its lower 3 dB frequency b) raises its upper 3 dB frequency c) increases its bandwidth d) all of the above 56. What changes would be necessary in block C if FM signals are to be received - a) Block becomes redundant b) A FM detector would be required c) A high frequency signal generator d) An additional local oscillator will be needed 57. The main disadvantage of Diode-Transistor logic (DTL) is its- a) greater speed b) slower speed c) average speed d) none of the above 58. Time delay Dt in digital signals in an SIS O shift register is given by ? a) Dt = N ? Fc b) Dt = N ? 1/Fc c) Dt = 1/N ? Fc d) Dt = N ? 1/Fc 59. The output Qn is 1 in a JK flip flop and it does not change when clock pulse is applied) The possible combination of Jn and Kn can be ? (y denotes don’t care) a) y and 0 b) y and 1 c) 0 and y d) 1 and y 60. Basic memory cell of dynamic RAM consists of ? a) a flip flop b) a transistor acting as a capacitor c) a transistor d) a capacitance 61. The 2′s complement of 10002 is ? a) 0111 b) 0101 c) 1000 d) 0001 62. Master slave flip-flop is made up of ? a) two flip flops connected in series b) two flip flops connected in parallel c) a debouncer circuit d) a-D- latch 63. Number of nybbles making one byte is ? a) 2 b) 4 c) 8 d) 16 64. The intrinsic impedance of free space- a) is independent of frequency b) decreases with increase of frequency c) increases with increase of frequency d) varies as square root of frequency 65. A system consists of 12 poles and 2 zeroes. Its high frequency asymptote in its magnitude plot has a slope of - a) ?200 dB/decade b) ?240 dB/decade c) ?230 dB/decade d) ?320 dB/decade 66. Considering the conditions- 1. High loop gain 2. Less ringing 3. Greater damping 4 Negative dB gain margin System stability requirements would include a) 1 and 3 b) 1, 2 and 3 c) 1 and 4 d) 2, 3 and 4 67. In the equatorial plane only Geosychronous satellite are launched because it is the only plane which provides ? a) 24 hour orbit b) stationary satellite c) global communication d) zero-gravity environs 68. Radio Broadcasting is an example of ? a) space multiplexing b) time multiplexing c) frequency multiplexing d) none of the above 69. PAM signals can be demodulation by using a ? a) Low pass filters (LPE) alone b) A Schmitt trigger followed by a LPF c) A differentiator followed by a LPF d) A clipper circuit by a LPF 70. In an FDM receiver channels can be separated by using ? a) AND gates b) Band pass c) differentiation d) Integration 71. The most common modulation system used for telegraphy is- a) frequency shift keying b) two ? tone modulation c) pulse code modulation d) single tone modulation 72. Use of varoctor diode in generation of modulated segial be- a) FM generation only b) 100AM generation only c) PM generation only d) both PM and AM generation 73. In colour picture tube shadow mask is used to- a) reduce x-ray emission b) ensure that each beam strikes only its own dots c) increase screen brightness d) provide degaussing for the screen 74. The circuit that separates composite video warefore from the sync pulses is- a) the keyed AGC amplifar b) a clipper c) an integrator d) a sawtooth current 75. Band width of microwaves is- a) 1GHz -103 GHz b) 1GHz ?100 GHz c) 1 GHz ?10 GHz d) 1 GHz ? 106 GHz 76. In transverse Magnetic mode- a) no electric line is in direction of propagation b) no magnetic line is in direction of propagation c) bath magnetic & electric lines are is direction of propagation d) neither magnetic nor electric lines in direction of propagation 77. Signal transmission in sky wave propagation is due to ? a) Reforction of wave b) Reflection of wave c) Pierus through Inosphere d) None 78. According to Barkhausen Criterion Phase shift of signal should be ? a) 600 b) 900 c) 1800 d) 3600 79. The transmission does not have - a) Partition noise b) Flicker noise c) resistance d) Short noise 80. Varoctor diode has non linearity of - a) capacitance b) Inductance c) Resistance d) Is a linear device 81. Noise figure is calculated as ? a) i/p signal to noise ratio X o/p signal to noise ratio b) i/p S/N Ratio / O/P S/N Ratio c) i/p S/N Ratio / O/P S/N Ratio X 100 d) i/p S/N Ratio + O/P S/N Ratio 82. You can determine quickly the effect of adding poles and zeros by ? a) Nicholas chart b) Nyquist plot c) Bode plot d) Root locus. 83. The polar plot of G(S) = intercepts real axis at w = wo. Then, the real part and wo are given by- a) ?5, 1 b) ?2.5, 1 c) ?5,0-5 d) ?5, 2 84. Laplace transform F (s) of a function f (E) is given by The initial and final values of F (t) will be respectively- a) zero and 1 b) zero and 10 c) 10 and zero d) 70 and 80 85. A satellite link uses different frequencies for receiving and transmitting in order to ? a) avoid interference from terrestrial microwave links b) avoid interference between its powerful transmitted signals and weak in coming signal c) minimize free-space losses d) maximize antenna gain 86. The first determining factor in selecting a satellite system is its- a) EIRP b) Antenna size c) Coverage area d) Antenna gain 87. Equalizing pulses in TV are sent during- a) horizontal blanking b) vertical blanking c) the serrations d) the horizontal retrace 88. The son seems to have ——– from his father a somewhat gloomy and moody manner- a) washed b) inherited c) admired d) attempt 60. Basic memory cell of dynamic RAM consists of ? a) a flip flop b) a transistor acting as a capacitor c) a transistor d) a capacitance 61. The 2′s complement of 10002 is ? a) 0111 b) 0101 c) 1000 d) 0001 62. Master slave flip-flop is made up of ? a) two flip flops connected in series b) two flip flops connected in parallel c) a debouncer circuit d) a-D- latch 63. Number of nybbles making one byte is ? a) 2 b) 4 c) 8 d) 16 64. The intrinsic impedance of free space- a) is independent of frequency b) decreases with increase of frequency c) increases with increase of frequency d) varies as square root of frequency 65. A system consists of 12 poles and 2 zeroes. Its high frequency asymptote in its magnitude plot has a slope of - a) ?200 dB/decade b) ?240 dB/decade c) ?230 dB/decade d) ?320 dB/decade 66. Considering the conditions- 1. High loop gain 2. Less ringing 3. Greater damping 4 Negative dB gain margin System stability requirements would include a) 1 and 3 b) 1, 2 and 3 c) 1 and 4 d) 2, 3 and 4 67. In the equatorial plane only Geosychronous satellite are launched because it is the only plane which provides ? a) 24 hour orbit b) stationary satellite c) global communication d) zero-gravity environs 68. Radio Broadcasting is an example of ? a) space multiplexing b) time multiplexing c) frequency multiplexing d) none of the above 69. PAM signals can be demodulation by using a ? a) Low pass filters (LPE) alone b) A Schmitt trigger followed by a LPF c) A differentiator followed by a LPF d) A clipper circuit by a LPF 70. In an FDM receiver channels can be separated by using ? a) AND gates b) Band pass c) differentiation d) Integration 71. The most common modulation system used for telegraphy is- a) frequency shift keying b) two ? tone modulation c) pulse code modulation d) single tone modulation 72. Use of varoctor diode in generation of modulated segial be- a) FM generation only b) 100AM generation only c) PM generation only d) both PM and AM generation 73. In colour picture tube shadow mask is used to- a) reduce x-ray emission b) ensure that each beam strikes only its own dots c) increase screen brightness d) provide degaussing for the screen 74. The circuit that separates composite video warefore from the sync pulses is- a) the keyed AGC amplifar b) a clipper c) an integrator d) a sawtooth current 75. Band width of microwaves is- a) 1GHz -103 GHz b) 1GHz ?100 GHz c) 1 GHz ?10 GHz d) 1 GHz ? 106 GHz 76. In transverse Magnetic mode- a) no electric line is in direction of propagation b) no magnetic line is in direction of propagation c) bath magnetic & electric lines are is direction of propagation d) neither magnetic nor electric lines in direction of propagation 77. Signal transmission in sky wave propagation is due to ? a) Reforction of wave b) Reflection of wave c) Pierus through Inosphere d) None 78. According to Barkhausen Criterion Phase shift of signal should be ? a) 600 b) 900 c) 1800 d) 3600 Last edited by Anuj Bhola; October 10th, 2019 at 12:09 PM. |
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August 16th, 2014, 09:27 AM
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| Re: BSNL-TTA Examination Solved Question papers
79. The transmission does not have - a) Partition noise b) Flicker noise c) resistance d) Short noise 80. Varoctor diode has non linearity of - a) capacitance b) Inductance c) Resistance d) Is a linear device 81. Noise figure is calculated as ? a) i/p signal to noise ratio X o/p signal to noise ratio b) i/p S/N Ratio / O/P S/N Ratio c) i/p S/N Ratio / O/P S/N Ratio X 100 d) i/p S/N Ratio + O/P S/N Ratio 82. You can determine quickly the effect of adding poles and zeros by ? a) Nicholas chart b) Nyquist plot c) Bode plot d) Root locus. 83. The polar plot of G(S) = intercepts real axis at w = wo. Then, the real part and wo are given by- a) ?5, 1 b) ?2.5, 1 c) ?5,0-5 d) ?5, 2 84. Laplace transform F (s) of a function f (E) is given by The initial and final values of F (t) will be respectively- a) zero and 1 b) zero and 10 c) 10 and zero d) 70 and 80 85. A satellite link uses different frequencies for receiving and transmitting in order to ? a) avoid interference from terrestrial microwave links b) avoid interference between its powerful transmitted signals and weak in coming signal c) minimize free-space losses d) maximize antenna gain 86. The first determining factor in selecting a satellite system is its- a) EIRP b) Antenna size c) Coverage area d) Antenna gain 87. Equalizing pulses in TV are sent during- a) horizontal blanking b) vertical blanking c) the serrations d) the horizontal retrace 88. The son seems to have ——– from his father a somewhat gloomy and moody manner- a) washed b) inherited c) admired d) attempt 89. Essayist works with words as sculptor with- a) water b) stone c) air d) hills 90. What is a collection of sheep called ? a) bunch b) flock c) herd d) comet 91. Join these sentences meaningfully by choosing the correct alternative from the following : You can buy a book. You can read it. a) and b) nor c) either d) neither 92. What is the opposite of Asperity ? a) gentility b) superiority c) kindness d) clarity 93. The Election Commission functions under- a) Ministry of Home Affairs b) Ministry of Law c) Prime Minister’s Secretariat d) None of these 94. Article 352 of Indian Constitution needs to be revoked in case- a) President’s Rule is to be imposed b) Emergency is declared c) Services of a Government servant are to be terminated without any enquiry d) A political party of national level is to be banned 95. Radio-activity was first discovered by- a) Becquerel b) Madam Curie c) Rutherford d) Jenner 96. Ninth Plan in India ranges from- a) 1995-2000 b) 1996-2001 c) 1997-2002 d) 1998-2003 97. How much electricity does India propose to generate through nuclear power by the year 2000 AD? a) 5,000 MW b) 10,000 MW c) 15,000 MW d) 20,000 MW 98. In which year did the fall of Bastille take place? a) 1769 b) 1789 c) 1889 d) 1869 99. To form a quorum how many members of the Lok Sabha or Rajya Sabha should be present? a) 1/10th of total membership b) 1/6th of total membership c) 1/4th of total membership d) 1/5th of total membership 100. How may countries are non-permanent members of the Security Council? a) 6 b) 7 c) 9 d) 10 1. If the matrix A = is singular, then ? = a) 3 b) 4 c) 2 d) 5 2. A = is symmetric, then x = a) 3 b) 4 c) 2 d) 5 3. If A is a 3 x 3 matrix and det(3 A) = k det(A) then k = a) 9 b) 6 c) 1 d) 27 4. If A = , then A-1 = a) b) c) d) 5. If A = then A2 is equal to a) A b) –A c) Null Matrix d) I 6. is a a) rectangular matrix b) singular matrix b) non-singular matrix d) skew-symmetric matrix 7. The slope of the straight line whose inclination with negative x-axis is 120º is a) b) c) 1 d) infinity 8. If two lines whose slopes are m1 and m2 are perpendicular iff a) m1 = m2 b) m1m2 = 0 c) m1m2 = -1 d) m1 + m2 = -1 9. The rate of increase of the radius of a circle is 1 cm/sec, the rate of increase of its area is 4? cm2/sec at a particular instant. The radius at that instant is a) 2 cm b) 3 cm c) 4 cm d) 6 cm 10.If the side of a square is increasing at the rate of 0.02 cm/min, the rate at which its area is increasing at the instant when the length of the side is 5 cm is a) 0.2 cm 2/min b) 0.4 cm 2/min c) 0.1 cm 2/min d) 0.6 cm 2/min 11.A particle is moving on a plane according to the distance-time relationship is given by s = t3 + 6t2 + 8t – 4. When its acceleration is 8 m/sec2, its velocity is a) 8 m/sec b) 11 m/sec c) 23 m/sec d) -1 m/sec 12.A stone moves vertically upwards according to the distance-time equation s = 16t – 2t2.The greatest height reached by the stone is a) 4 b) 64 c) 32 d) 96 13.The distance moved by a particle traveling in a straight line in t seconds is given by s = 45t + 11t2 – t3. The time taken by the particle to come to rest is a) 9 sec b) 5 sec c) 3 sec d) 2 sec 14.The distance s described by a particle in time t is given by the relation s = aet + be-t. The acceleration is equal to a) velocity b) the distance traveled c) twice the distance traveled d) the square of the distance traveled 15.The slope of the normal to the curve y = at the point is a) 9 b) -9 c) d) 17.The normal to the curve y = f(x) will be parallel to x-axis if a) b) c) d) 18.The maximum point of the function 2×3 – 9×2 + 12x is a) x = 0 b) x = 5 c) x = 1 d) x = 2 19.The minimum value of 2×3 – 9×2 + 12x – 4 is a) 1 b) 3 c) 0 d) -2 20.The point of inflection of the function x3 – 3×2 + 3x is a) (1,0) b) (1,1) c) (6,126) d) (-1,-7) 21.Velocity of sound is greatest in a) Solids b) Liquids c) Gases d) None of these 22.If the phase difference between the two waves is 2? during superimposition, then the resultant amplitude is a) Maximum b) Minimum c) Half of maximum d) None of these 23.If two waves of same frequency and same amplitude on superimposition produce a resultant disturbance of the same amplitude, the wave differ in phase by a) b) c) d) 24.The equation of a plane progressive wave is given by y = 2sin?(0.5x – 200t) where x and y are expressed in cm and t in sec. The wave velocity is a) 400 cm/sec b) 300 cm/sec c) 200 cm/sec d) 100 cm/sec 25.Equation of a plane progressive wave is given by y = 0.2 cos ?(0.04t + 0.02x – 1/6). The distance is expressed in cm and time in sec. The minimum distance between two particles separated by phase difference ?/2 is radian is a) 25 cm b) 12.5 cm c) 8 cm d) 4 cm 26.Ultrasonic waves are those waves which a) Human being can hear b) Human being cannot hear c) Have high velocity d) Have large amplitude 27.It is possible to distinguish between the transverse and longitudinal waves by studying the property of a) Interference b) Polarization c) Diffraction d) Reflection 28.The following phenomenon cannot be observed for sound waves a) Refraction b) Polarization c) Diffraction d) Reflection 29.Doppler shift in frequency does not depend upon a) Frequency of the wave produced b) Velocity of the source c) Velocity of the listener/observer d) Distance between source and listener 30.A source of sound of frequency 450 cycles/second is moving towards a stationary observer with 34 m/s speed. If the speed of sound is 340 m/s then the apparent frequency will be a) 410 cps b) 550 cps c) 500 cps d) 450 cps 31.An observer moves towards a stationary source of sound of frequency n. The apparent frequency heard by him is 2n. If the velocity of sound in air is 332 m/s, then the velocity of observer is a) 166 m/s b) 664 m/s c) 332 m/s d) 1328 m/s 32.The equation of a wave traveling in a string can be written as y = 3 cos ?(100t – x).Its wavelength is a) 100 cm b) 5 cm c) 3 cm d) 2 cm 33.Sound velocity is maximum in a) O2 b) H2 c) He d) N2 34.Phon is the unit of a) Pitch b) Quality c) Timbre d) Loudness 35.Loudness of sound L and corresponding intensity of sound I are related as a) L = KI2 b) L = KI c) L = K d) L = K log I 36.The index of refraction of a medium is 1.5. If the speed of light in air is 3 x 108 m/s, then its speed in the medium will be a) 2 x 108 m/s b) 1.2 x 108 m/s c) 4 x 108 m/s d) 3.2 x 108 m/s 37.The ratio of intensities of the two waves is given by 4:1. The ratio of amplitudes of two waves is a) 2:1 b) 1:2 c) 4:1 d) 1:4 38.Two source of waves are called coherent if a) Both have the same amplitude by vibrations b) Both produce waves of different wavelength having constant phase difference c) Both produce waves of same wavelength having constant phase difference d) Both produce waves having the same velocity 39.Which of the following does not support the wave nature of light? a) Interference b) Diffraction c) Polarization d) Photoelectric effect 40.Velocity of light will be minimum in a) Vacuum b) Air c) Water d) Glass 41.Wavelength of light of frequency 100 Hz is a) 2 x 106 m/s b) 3 x 106 m/s c) 4 x 106 m/s d) 5 x 106 m/s 42.A rocket is going away from earth at a speed of 106 m/s. If the wavelength of the light wave emitted by it be 5700 Å, its Doppler’s shift will be a) 200 Å b) 19 Å c) 20 Å d) 0.2 Å 43.Colour of light is known by its a) Velocity b) Amplitude c) Frequency d) Polarization 44.A rocket is going away from the earth at a speed 0.2c where c = Speed of light. It emits a signal of frequency 4 x 107 Hz. The frequency observed by an observer on the earth will be a) 4 x 106 Hz b) 3.3 x 106 Hz c) 3 x 106 Hz d) 5 x 107 Hz 45.A light wave has a frequency of 4 x 1014 Hz and a wavelength of 5 x 10-7 m in a medium. The refractive index of the medium is a) 1.5 b) 1.33 c) 1.0 d) 0.66 46.Stars are twinkling due to optical phenomenon of a) Refraction b) Scattering c) Reflection d) Diffraction 47.The splitting of white light into several colours on passing through a glass prism is due to a) Refraction b) Reflection c) Interference d) Diffraction 48.In Bohr’s model, if the atomic radius of the first orbit is ro, then the radius of the fourth orbit is a) 16 ro b) ro c) 4 ro d) ro/16 49.The average binding energy per nucleon in the nucleus of an atom is approximately a) 8 eV b) 8 MeV c) 8 KeV d) 8 Volt 50.The mass equivalent of 931 MeV energy is a) 1.66 x 10-20 kg b) 1.66 x 10-27 kg c) 6.02 x 10-24 kg d) 6.02 x 10-27 kg 51.The energy equivalent to 1 a.m.u. is a) 931 MeV b) 931 eV c) 931 KeV d) 9.31 MeV 52.The ratio of kinetic energy and total energy of an electron in a Bohr orbit is a) + 2 b) – 1 c) + 1 d) – 2 53.The size of an atom is of the order of a) 1 Å b) 1 fermi c) 1 nm b) 1 micron 54.The mass defect per nucleon is called a) Packing fraction b) Binding Energy c) Ionization Energy d) Excitation Energy 55.Nuclear Binding Energy is equal to a) Mass of Nucleus b) Mass defect of Nucleus c) Mass of Proton d) Mass of Neutron 56.The Pfund series of Hydrogen spectrum lies in the region a) Infrared b) Visible c) Ultraviolet d) X-Ray 57.The number of neutrons in 92U238 is a) 92 b) 238 c) 330 d) 146 58.The energy required to remove an electron in a hydrogen atom from n = 10 state is a) 136.0 eV b) 13.60 eV c) 1.36 eV d) 0.136 eV 59.The angular momentum of electron in nth orbit is given by a) b) c) d) 60.The rest energy of an electron is a) 510 MeV b) 51 MeV c) 931 MeV d) 93.1 MeV 61.In the lowest energy level of hydrogen atom, the electron has the angular momentum a) ?/h b) h/? c) h/2? d) 2?/h 62.Laser is working in the principle of a) Stimulated emission of radiation b) Spontaneous emission of radiation c) Population inversion d) Normal population 63.The output beam of Ruby Laser has the wavelength of a) 6943 Å b) 6328 Å c) 6300 Å d) 5500 Å 64.In the He-Ne Laser , the He-Ne in the mixture of a) 10:1 b) 2:1 c) 4:1 d) 5:1 65.The full form of LIDAR is a) Light Amplitude and Ranging b) Light Detection and Ranging c) Light Defect and Ranging d) Laser Detection and Ranging 66.Which one of the following is solid state laser? a) Nd:YAG Laser b) He-Ne Laser c) CO2 Laser d) GaAs Laser 67.Populaton Inversion is achieved by means of a) Optical pumping b) Gas pumping c) Mechanical pumping d) Solid pumping 68.GRASERS are a) Galium Arsenide Lasers b) Gamma Ray Lasers c) General Ranging Lasers d) Gallium Radium Lasers 69.LASER Beam is a) Highly monochromatic b) Highly Intense c) Highly Coherent d) All of the above 70.Which one of the following cannot be used as a pulsed device? a) CFA b) BWO c) TWT d) Magnetron 71.Klystron works in the principle of a) Velocity Modulation b) Amplitude Modulation c) Frequency Modulation d) Phase Modulation 72.Strapping in Magnetron is used to a) prevent mode jumping b) ensure bunching c) improve the phase focusing effect d) prevent cathode back heating 73.Which is not a TWT slow wave structure a) Coupled cavity b) helix c) ring bars d) periodic permanent magnet 74.30 to 300 MHz frequency range is categorized as a) MF b) VHF c) UHF d) SHF 75.Find the centre of the circle whose two extremities of diameter are (2,3) & (4,-1) is a) (3,1) b) (6,8) c) (3,-2) d) (-6,8) 76.The centre and radius of the circle x2+y2+4x–6y+2=0 are a) (-2,3) & 5 b) (-2,3) & 5 c) (2,-3) & 5 d) (2,-3) & 2 77.The angle between the straight lines x + 2y -3 = 0 & 2x + 4y -4 = 0 is a) ? = 90º b) ? = 60º c) ? = 0º d) ? = 45º 78.The condition for the pair of straight lines ax2+2xy+by2+2x+2y+3=0 to be perpendicular is a) h2–ab = 0 b) ab = 2 c) a+b = 0 d) a-b = 0 79.The particular integral of +3 + 2y = 2e-x is a) 2xe-x b) 2e-x c) x2e-x d) xe-x 80.The particular integral of +4 + 4y = 3sin2x is a) – cos2x b) cos2x c) sin2x d) 3xcos2x 81.The complementary function of (D2+3)y = e-x is a) Ae x + Be x b) (A+Bx) e x c) A cos3x + B sin3x d) A cos x + B sin x 82.The solution of (D2-2D-15)y = 0 is a) y = Ae3x + Be5x b) y = Ae-3x + Be-5x c) y = Ae5x + Be-3x d) y = Ae-5x + Be3x 83.The particular integral of + y = 3 is a) 3 b) x/3 c) 3/y d) -3 84.The area bounded by x2 = 2y, the x-axis and the lines x = 1 and x = 3 is a) b) c) d) 85.The area of the curve y = sin x bounded by the x-axis from x = 0 to x = 2? is a) 0.5 b) 1.0 c) 1.5 d) 2.0 86.The area enclosed by the curve xy = 8 and x-axis from x = 1 to x = 4 is a) 8 log 2 b) 16 log 2 c) 4 log 2 d) 2 log 4 87.The area bounded by the curve x = 3y2 – 9 and the lines x = 0, y = 0 and y = 1 is a) 8 b) c) d) 3 88.When the area enclosed by the curve y = and the x-axis from x = 0 and x = 4 is rotated about the x-axis, the volume generated is a) b) c) d) 89.The area included between the curve y = x – x2 and the x-axis revolves about the x-axis. The volume generated by the area is a) b) c) d) 90.If the area enclosed between the curve y2 = x3 + 5x and the x-axis from x = 2 to x = 4 is revolved about the x-axis, the volume of the solid generated is a) 45? b) 90? c) 120? d) 60? 91. a) 12 b) 0 c) 6 d) 18 92. = a) sin-1x b) cos-1x c) tan-1x c) cot-1x 93. a) log f(x) b) 2 c) f(x) d) f(x)/2 94. a) sec x b) tan x c) cos x d) cot x 95.The acceleration of a particle at any time t is given by 3×2 – 2x + 1, then the velocity of the particle at any time is a) x3 -2x 2 + x b) x3 -x 2 + x c) x 2 + x d) x 2 + x +1 96.The Laplace transform of f(t) = t2 e-3t is a) b) c) d) 97.The Laplace transform of f(t) = 1 + cos2t is a) b) c) d) 98.The Laplace transform of unit step function is a) b) c) 1 d) 99.The initial value of the function F(S) = a) 1 b) 0 c) 2 d) 100.The inverse Laplace transform of is a) e-t b) 1-e-t c) 1- et d) 2(1+ e-t) 101.The inverse Laplace transform of is a) et cos2t b) et sin2t c) e-t cos2t d) e-t sin2t 102.(1+i)3 is equal to a) 3 + 3i b) 1 + 3i c) 3 – 3i d) 2i – 2 103.The value of i13+i14+i15+i16 is a) 0 b) -1 c) i d) –i 104. The polar form of complex number -1- i is a) 2(cos + i sin ) b) 2(cos + i sin ) b) 2(cos – i sin ) d) 2(cos + i sin ) 105.The modulus of a complex number is a) b) 2 c) 1 d) 106.The value of (3+?+3?2)4 is a) 16 b) 16 ? c) -16 ? d) 0 107.The value of is a) cos 2? + i sin 2? b) cos ? + i sin ? c) cos ? – i sin ? d) cos 26? + i sin 26? 108.The value of the fourier coefficient bn for the function f(x) = cosx defined in (-?, ?) is a) 0 b) 1 c) ? d) -2 ? 109. The value of the fourier coefficient a0 for the half range series for f(x) defined in (0, ?) is a) a0 = b) a0 = c) a0 = d) 0 110.The value of the fourier coefficient an for the function f(x) is odd is a) 0 b) an = c) an= d) a0 = 111.The value of the fourier coefficient bn for the function f(x) is even is a) 0 b) bn = c) bn = d) bn = 112.If u = exy then x a) u b) u logeu c) logeu d) ueu 113.If u = then the value of is a) b) 0 c) x+y d) -1 114.If u = sin-1 , then the value of is a) b) c) d) 115.If u = xy, then is a) y/x b) xyx-1 c) yxy-1 d) xy-1 116. Given = = 6 and . = 18, the angle between and is a) b) c) d) 117.( – ) x ( + ) = a) 2 x b) x c) 2 x d) 2 – 2 118.The volume of the parallelepiped whose three coterminous edges are represented by the vectors + , + , + is a) 2 b) 3 c) 4 d) 1 119.The value of p such that the vectors -2 + 3 , 4 +3 – and 11 +p + 7 are coplanar is a) -7 b) 0 c) -12 d) 12 120.Reverberation of sound means a) existence of sound in a room b) vibration of sound waves c) existence of sound eventhough the source of sound is cutoff d) strong echoes 121.Ultrasonic waves can be produced by a) Piezo-electric effect b) Inverse Piezo-electric effect c) Magnetostriction effect d) Both b & c 122.The Sabine’s formula for reverberation time is a) T = b) T = c) T = d) T = 0.16 aAS |
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