NATIONAL TRANSMISSION & DESPATCH COMPANY NTDCL Junior Engineer (BPS-17) Test Conducted on 22 August, 2021
The following multiple-choice questions are from the NTDCL Junior Engineer (BPS-17) Test conducted on August 22, 2021. These questions cover a range of topics relevant to electrical engineering, and they are essential for candidates preparing for positions at the NATIONAL TRANSMISSION & DESPATCH COMPANY (NTDCL). The bolded question statements aim to facilitate easy navigation, providing a comprehensive review of key concepts necessary for success in the NTDCL Junior Engineer examination.
Question 1: Common mode rejection ratio (CMRR) is defined as: A. Common mode gain at output to differential mode gain at output B. Common mode gain at input to differential mode gain at input C. Differential mode gain to common mode gain D. Common mode gain to differential mode gain
Question 2: The convergence characteristics of the Newton-Raphson method of solving a load flow problem is: A. Quadratic B. Geometric C. Cubic D. Linear
Question 3: The sum of all potential differences in a complete loop through the circuit should be: A. Equal to individual voltages B. Equal to zero C. Equal to individual resistances D. Equal to individual currents
Question 4: Transient state stability is generally improved by: A. Using low inertia machines B. Dispensing with neutral grounding C. Using high-speed governors on machines D. Any of the above
Question 5: The number of cycles in which a high-speed circuit breaker can complete its operation is: A. 10 to 18 B. 3 to 8 C. 40 to 50 D. 20 to 30
Question 6: If the firing angle in an SCR rectifier is decreased, output will be? A. Increased B. Unaffected C. Maximum D. Decreased
Question 7: Fourier series are infinite series of elementary trigonometric functions i.e. Sine and? A. Cosec B. Cosine C. Tan D. Sec
Question 8: A copper oxide _______________ allows current to flow through a meter in only one direction? A. Rectifier B. DIAC C. Transistor D. Voltmeter
Question 9: Stepper motor is a/an _______________ which divides full rotation into a large number of steps? A. Small B. Alternating current C. Direct Current D. Powerless
Question 10: Which instrument has the same calibrations for both AC and DC values? A. Moving iron type B. Induction type C. Hot wire type D. Moving coil type
Question 11: As compared to oscillators, inverters provide? A. Low frequency output B. Noiseless output C. Low voltage output D. Distortionless output
Question 12: A ________ can be used to make an automated potentiometer in comparison measurements? A. Electrostatic Voltmeter B. Digital to analog converter C. Analog to digital converter D. Electrometer
Question 13: The potential difference between the two similar charges? A. Infinite B. Same C. Nill D. Opposite
Question 14: In a power plant, coal is carried from storage place to boiler generally by means of? A. Trolleys B. V-Belts C. Manually D. Buckets
Question 15: Noise in resistance depends upon? A. Operating temperature B. Material C. All of these D. Sampling rate
Question 16: In a parallel resonance circuit, at resonance? A. Voltage is maximum B. Current is maximum C. Impedance is minimum D. Impedance is zero
Question 17: The radius of curvature of the path of a charged particle in a uniform magnetic field is directly proportional to? A. Particle’s charge B. Flux density of the field C. Particles Momentum D. Particules Energy
Question 18: The elements which absorb the energy are called “Passive Elements” like Resistance, inductance and? A. Capacitance B. Voltage C. Power D. Current
Question 19: A bridge which is used for the measurement of capacitance of an insulator? A. Maxwell bridge B. Shearing bridge C. Wheatstone bridge D. Wein’s bridge
Question 20: If the oscillations per minute of a rotor are 120 with a stator frequency of 50 Hz. Its slip will be? A. 4% B. 8% C. 10% D. 12%
Question 21: A large size alternator is protected against overloads by providing? A. Over voltage relays B. Thermal relays C. Over current relays D. Temperature sensitive relays
Question 22: The ratio error of a current transformer is due to the presence of? A. Corona effects B. Exciting currents C. Lagging power factor D. Stray magnetism
Question 23: In a radio receiver A. All stages contribute equally to noise B. RF stage has no effect on S/N ratio C. RF stage has effect on S/N ratio D. Mixer stage contributes most of the noise generated
Question 24: Hot wire anemometers are used to measure? A. Velocity of air stream B. Variable voltage C. Pressure of fluids D. Leakage reactance
Question 25: The letter DPDT is for? A. Thick wire B. Conductor C. Fuse D. Switch
Question 26: In transmission lines, the curve between discharge in m3/sec and time is called? A. Discharge duration curve B. Load curve C. Hectograph D. Hydrograph
Question 27: Power plants using coal work closely with which of the following cycle? A. Binary vapor cycle B. Otto cycle C. Brayton cycle D. Rankine cycle
Question 28: The air standard efficiency of a diesel engine depends upon? A. Speed B. Torque C. All of these D. Compression ratio
Question 29: Coking is A. Formation of lumps or masses of coke in boiler surface at high temperatures B. Producing lumps of coal from fine powders with the help of a binder C. Burning of coal in furnace D. Heating of coal in the absence of air, driving out CO2 and leaving behind the residue and carbon
Question 30: Deuterium oxide is used in nuclear reactors as? A. Moderator B. Regulator C. Fuel D. Shield
Question 31: The output of a solar cell is of the order of? A. 0.5 W B. 1 W C. 1.5 W D. 0.5 W
Question 32: The surge resistance of transmission lines is about? A. 800 ohm B. 100 ohm C. 400 ohm D. 50 ohm
Question 33: In high voltage transmission lines, the topmost conductor is? A. Y-phase conductor B. Earth conductor C. R-phase conductor D. B-phase conductor
Question 34: Skin effect in transmission lines is proportional to? A. (Diameter of conductor)4 B. (Diameter of conductor)1/4 C. (Diameter of conductor)2 D. Diameter of conductor
Question 35: Shunt capacitance is usually neglected in the analysis of? A. Medium and Long Transmission lines B. Long transmission lines C. Medium transmission lines D. Short transmission lines
Question 36: In order to reduce the skin effect at UHF? A. Conductors are painted B. Copper rods with silver plating are used C. Copper tubes with silver plating are used D. Conductors are anodized
Question 37: Transmission lines link A. Generating station to receiving end station B. Receiving end station to generating end station C. Service mains to consumer premises D. Distribution transformer to consumer premises
Question 38: The square law of a photodetector gives current. This current is proportional to_______ of the combined optical field? A. Square root B. Square C. Cube D. None of these
Question 39: The _________ is an electromagnetic carrier wave which is modulated to carry information? A. Sound B. Electricity C. Light D. Air
Question 40: Out of the following which one is not the unconventional source of energy? A. Tidal power B. Wind power C. Nuclear energy D. Geothermal energy
Question 41: In case the height of the transmission tower is increased A. The line capacitance and inductance will not change B. The line capacitance will decrease and line inductance will increase C. The line capacitance and inductance both are increased D. The line capacitance will decrease but line inductance will remain unaltered
Question 42: The instrument which used for DC measurement alone is? A. Induction type B. Permanent magnet type C. Electrodynamic type D. Moving Iron type
Question 43: Conductors have an excess of? A. Electrons B. Neutrons C. Free electrons D. Protons
Question 44: Super-heated steam is always? A. Separated from water particles before being supplied to the turbine B. At a pressure less than the maximum cycle pressure C. At a pressure more than the boiler steam pressure D. At a temperature higher than the saturation temperature corresponding to a steam pressure
Question 45: ___________ is the source that gives constant voltage (V=E) no matter how much current is drawn from it? A. Ideal resistance source B. Real voltage source C. Real voltage and current source D. Ideal current source
Question 46: A tunnel diode is A. A heavily doped PN junction device B. A lightly doped PN junction device C. Has a small tunnel in its junction D. Is a gallium arsenide device
Question 47: Potential has a unit? A. Farad B. Watt C. Volt D. Ampere
Question 48: The turn-on voltage of a germanium diode is? A. 0.7 V B. 0.3 V C. 0.1 V D. 1.0 V
Question 49: Steam engine used in a locomotive is? A. Single acting, condensing type B. Single acting, non-condensing type C. Double acting, condensing type D. Double acting, non-condensing type
Question 50: Pressure of steam in the condenser is? A. Atmospheric pressure B. More than pressure C. Slightly less than pressure D. Much less than pressure
Question 51: Which comparison is correct between a fluorescent lamp and a filament bulb? A. Average life of a fluorescent lamp is five to seven times higher B. Fluorescent lamp produces more brightness C. Fluorescent lamp produces more sharp shadows D. Fluorescent lamp has higher dazzle
Question 52: To carry a current of 100 RMS, the area of the Aluminum bus bar must be at least? A. 25 mm2 B. 1 mm2 C. 10 mm2 D. 50 mm2
Question 53: A short transmission line has an equivalent circuit consisting of? A. Series inductance L and shunt capacitance G B. Series resistance R and shunt capacitance G C. Series resistance R and shunt capacitance C D. Series resistance R and series inductance L
Question 54: The characteristics impedance of a transmission line depends upon which of the following? A. Geometrical configuration of conductors B. Conductivity of the material C. Surface treatment of conductors D. Shape of the conductors
Question 55: The peak value of the power angle curve of a transmission line is 50 MVA. If two such identical lines are added in parallel, the resulting peak value is? A. 100 MVA B. 25 MVA C. 50 MVA D. 200 MVA
Question 56: A phase modifier is normally installed in the case of? A. Short transmission lines B. Medium transmission lines C. Long transmission lines D. All-length lines
Question 57: For stability and economic reasons, we operate the transmission line with a power angle in the range of? A. 10 to 20 B. 30 to 45 C. 60 to 75 D. 65 to 80
Question 58: How many roots does a quadratic equation have? A. 1 B. 2 C. 3 D. 4
Question 59: Which operation is not performed on independent variables? A. Time shifting B. Time reversal C. Time scaling D. Amplitude scaling
Question 60: How many interrupts does the 8085 microprocessor have? A. 2 B. 3 C. 4 D. 5 (NTS not clearly mentioned which interrupts either Hardware or Software. Hardware has 5 interrupts while software has 8)
Question 61: The ratio of collector current to the reverse saturation current is known as? A. Efficiency of transistor B. Transistor stability factor C. Operating point of transistor D. Amplification factor of transistor
Question 62: Conductivity of the wire depends upon? A. Resistance B. Free Electron density C. Area of conductor D. All of these
Question 63: For what purpose is a moderator used in nuclear power plants? A. Stop the chain reaction B. Accelerate the speed of neutrons C. Reduce the speed of neutrons D. To absorb neutrons
Question 64: Silicon has its atomic number 14, its valency is? A. 2 B. 3 C. 4 D. 5
Question 65: Memory locations that are used temporarily during program execution from R/W memory? A. Register B. Program pointer C. Stack pointer D. None of these
Question 66: Semiconductors belong to which group of the periodic table? A. Group III B. Group IV A C. Group IV B D. Group V A
Question 67: Which of the following does not use the effect of current for measurement purposes? A. Electrostatic ammeter B. Moving coil ammeter C. Hot wire ammeter D. Rectifier ammeter
Question 68: The DC equivalent circuit of an amplifier can be obtained by considering the capacitance? A. Open circuited B. Short circuited C. Partially short circuited D. None of these
Question 69: AC motors are of two types, induction motor and? A. Asynchronous motor B. Synchronous motor C. Shunt motor D. Both A and B
Question 70: A system that can recover its input from its output signal is known as? A. Invertible system B. Discrete system C. Transient system D. None of these
Question 71: If a dice is rolled 20 times, what is the probability of getting 15 or more heads? A. 0.024 B. 0.046 C. 0.241 D. 0.427
Question 72: As steam expands in a turbine A. Its pressure increases B. Its specific volume increases C. Its boiling point increases D. Its temperature increases
Question 73: Step-up substations are associated with? A. Distributors B. Consumer location C. Concentrated load D. Generating stations
Question 74: Which of the following is not installed in a substation? A. Shunt reactors B. Exciters C. Voltage transformers D. Series capacitors
Question 75: DC generators have ________ on rotating shafts that convert AC into DC? A. Diodes B. Commutators C. Brushes D. Rotor
Question 76: Which of the following is the stationary part of electrical machines? A. Stator B. Rotor C. Commutator D. None of these
Question 77: Schmitt trigger produces ___________ at the output when the input applies a sine wave? A. Triangular wave B. Square wave C. Sawtooth wave D. Non-sinusoidal wave
Question 78: If a network satisfies homogeneity condition as well as superposition condition, then it is said to be? A. Linear system B. Non-linear system C. Both A & B D. None of these
Question 79: Piezo-electric crystal is used to measure? E. Temperature F. Velocity G. Acceleration H. Flow of charge
Question 80: Precision measurement of resistance is measured generally carried out by? A. Voltmeter method B. CRO method C. Potentiometer method D. AC bridge method
Question 81: How many basic types of generators? A. 1 B. 2 C. 3 D. 4
Question 82: Which of the following transducers does not convert velocity to pressure? A. Orifice B. Venturi C. Pilot tube D. Vanes
Question 83: In a synchronous motor, rotor current is provided by …………….? A. Rotor B. DC Current source C. AC Current Source D. None
