Solved questions preview paper (2) 51-100

Q.51. The magnitude of induced EMF in a coil is directly proportional to the rate of change of flux linkage. This is known as

a.) Joule's law
b.) Faraday's second law of electromagnetic induction✔
c.) Faraday's first law of electromagnetic induction
d.) Coulomb's Law

Q.52. The magnetic potential in a magnetic circuit can be measured in term of
a.)mmf✔
b.)emf
c.)Farad
d.)Coulomb

Q.53. The point in a magnet where the intensity of magnetic lines of force is maximum
a.) Magnetic pole✔
b.) South Pole
c.) North Pole
d.) Unit pole

Q.54 which of the following magnetic materials can be easily magnetized in both direction
a.) Soft magnetic materials✔
b.) Hard magnetic material
c.) High hysteresis lost materials
d.) No hysteresis loss materials

Q.55 the current of electric circuit is analogous to which quantity of a magnetic circuit
a.) MMF
b.) Flux✔
c.) Flux density
d.) Reluctivity

Q.56. The ability of material to conduct magnetic flux through it
a.) Permittivity
b.) Reluctivity
c.) Conductivity
d.) Permeability✔

Q.57 small voltage generated by a conductor with current in an external magnetic field
a.) Skin effect
b.) Magnetic effect
c.) Hall effect ✔
d.) Flywheel effect

Q.58 A length of wire has a resistance of 10 ohms what is the resistance of a wire of the same material three times as long and twice the cross-sectional area
a.)30ohms
b.)20ohms
c.)15ohms✔
d.)7ohms

Q.59. The ratio of w W/VA in an AC circuit means
a.) Power factor✔
b.) Reactive power
c.) Quality factor
d.) Load factor

Q.60.Kirchhoff's laws (KCL and KVL) are applicable to
a.) DC circuit
b.) AC circuit
c.) DC as well as AC circuit✔
d.) Passive networks alone

Q.61. What is considered as the most important Value of A sine wave
a.) Effective value✔
b.) Peak value
c.) Average value
d.) Instantaneous value

Q.62. The voltage leg the current by pi/2. cycle in a
a.) Purely resistive circuit
b.) Purely inductive circuit
c.) Purely capacitive circuit✔
d.) Circuit containing resistance capacitance and inductance

Q.63 For a series circuit the higher the quality factor
a.) The greater the bandwidth
b.) The narrow the pass band✔
c.) The broader the business curve
d.) The wider the pass band

Q.64 voltage resonance means
a.) Series resonance✔
b.) Parallel resonance
c.) Current magnification
d.) Gain magnification

Q.65 which component oppose voltage change
a.) Resistor
b.) Inductor
c.) Capacitor✔
d.) Transistor

Q.66 a transistor configuration with the lowest current gain
a.) Common base✔
b.) Common emitter
c.) Common collector
d.)Emitter follower

Q.67 there are two mechanism by which holes and electrons move through a silicon crystal they are
a.) Covalent bond and recombination
b.) Diffusion and drift✔
c.) Free and charged particles
d.) Forward and reverse bias

Q.68 the peak inverse voltage of a full wave Centre tapped rectifier circuit is equal to ________of the input signal
a.) Thrice the peak
b.) Twice the peak✔
c.) One-half
d.) One third

Q.69. Which of the following has the least noise level
a.)FET✔
b.)BJT
c.)Triode
d.Tetrode

Q.70. Asynchronous motor always run at synchronous speed because
a.) Of the action ofamorstisseur  winding
b.) The lenz's law can not be violated
c.) Of magnetic locking between the stator and Rotor✔
d.) None of these

Q.71. The rotor of three phase induction motor always runs at
a.) Synchronous speed
b.) Less than synchronous speed✔
c.) More than synchronous speed
d.) None of these

Q.72. If one of the three phase of a three phase induction motor is disconnected while running at light load it will
a.) Stop running
b.) Continue to run at same speed✔
c.) Run at low speed
d.) Run at high speed

Q.73. If a three phase induction motor runs on 2 phase supply it will
a.) Run at low speed
b.) Run with jerks
c.) Likely to burn✔
d.) Blow off the fuses

Q.74.Majority of the induction motor have
a.) Totally enclosed frame
b.) Totally enclosed when closed frame✔
c.) Drip proof type frame
d.) None of these

Q.75.Which motor  is widely used
a.) Squirrel cage induction motor✔
b.) Slip ring induction motor
c.) Wound rotor synchronous motor
d.) Salient pole  synchronous motor

Q.76 The scale of moving iron instrument is
a.) Uniform
b.)Cramped✔
c.) First uniform then conjested
d. None of these

Q.77. For increasing the range of voltmeter connect a
a.) High value resistance in series with voltmeter✔
b.) Low value resistance in series with voltmeter
c.) High value resistance in parallel with voltmeter
d.) Low value business in parallel with voltmeter

Q.78. The most commonly used type of single phase energy metre is
a.) Dynamometer
b.) Electrostatic type
c.) Induction type✔
d.) Moving coil type

Q.79. In steam power plant water is used for pulling purpose in
a.) Condenser✔
b.) Turbine only
c.) Boiler tubes
d.) Both B and C

Q.80. A Kaplan turbine is
a.) Inward flow impulse turbine
b.) Outward flow reaction turbine
c.) A high head mixed flow turbine
d.) Low head axial flow turbine✔

Q.81. Nuclear reactor generally employs
a.) Fusion
b.) Fission✔
c.) Both A and B
d.) None of these

Q.82 In a fuel cell electricity is produced by
a.) Combustion of fuel in absence of oxygen
b.) Oxidation of fuel✔
c.) Thermionic
d.) None of these

Q.83. The corona effect can be minimised by increasing
a.) The length of the conductor
b.) Spacing between the conductors
c.) Diameter of the conductors
d.) Both spacing between conductors and diameter of the conductors✔

Q.84. Power can be transferred only If reactance is
a.) Absent
b.)Present✔
c.)Zero
d.)None  of these

Q.85. In a three phase system the phasor form of phase current is zero. It means absence of
a.) Positive sequence component
b.) Negative sequence component
c.) Zero sequence component✔
d.) All of these

Q.86 switching protection are undertaken by.
a.) Switchgear✔
b.) Lightning arrester
c.) Fuse
d.) Relays

Q.87.Switching surge
a.)High voltage DC
b.)High voltage AC
c.)Short duration transient voltage✔
d.)Low impedance voltage

Q.88. The impurity in a liquid dielectric, which has significant effect in reducing the breakdown strength is
a.)Dust✔
b.)Dissolved
c.)Moisture
d.)None of these

Q.89.In what are long ,EHV transmission lines in interconnected power system generally protected
a.)Over current protection
b.)Pilot protection✔
c.)Distance protection
d.)Differential protection.

Q.90. The most economic load on an overhead line is
a.) Less than the natural load
b.) Equal to the natural load
c.) Greater than the natural load✔
d.) None of these

Q.91. The characteristics of drive for crane hosting is
a.) Smooth movement
b.) Precise control
c.) Fast speed control
d.) All of these✔

Q.92. Non metallic conduit wiring generally made of
a.) Rubber
b.) Cork
c.) Wood
d.) PVC✔

Q.93.Inside the earth or pit, the earthing electrode should be placed
a.)Vertical✔
b.)Horizontal
c.)Inclined at 45°
d.)Inclined at any angle other then45°

Q.94.In three phase half wave rectifier, each diode conducts for a duration of
a.)180°
b.)30°
c.)60°✔
d.)45°

Q.95. During forward blocking state , a thyristor is associate with
a.)Large current ,low voltage
b.)Low current ,large voltage✔
c.)Medium current, large voltage
d.)None of these

Q.96.The liberation of electrons from the surface of a substance is called
a.)Bombardment of electron
b.)Electronic emission✔
c.)Movement of free electrons
d.)Ion emission

Q.97.The work function of metal is generally expressed in
a.)Joules
b.)Volts
c.)Electrons
d.)Electron volts✔

Q.98.Then 2's complement of the number 0111 is
a.)11001✔
b.)11000
c.)00011
d.)11111

Q.99. What is the base of hexadecimal number system?
a.)10
b.)8
c.)16✔
d.)9

Q.100. One  cloulomb is equal to
a.)6×10^12 electrons
b.)6×10^10 electrons
c.)6×10^15 electrons
d.)6×10^18 electrons✔