0% 0 Electrical Engineering Quiz 8 1 / 50 RC coupling is not used to amplify extremely low frequencies because____________? There is hum in the output Electrical size of coupling capacitor becomes very large There is considerable power loss None of the above 2 / 50 By looking at which part of the motor, it can be easily confirmed that a particular motor is D.C. motor? Commutator Stator Shaft Frame 3 / 50 The property of coil by which a counter e.m.f. is induced in it when the current through the coil changes is known as__________? series aiding inductance mutual inductance capacitance self-inductance 4 / 50 Life of the Edison cell is at least_____________? seven years eight years five years ten years 5 / 50 If the sheet of a bakelite is inserted between the plates of an air capacitor, the capacitance will__________? remains unchanged become zero increase decrease 6 / 50 Which of the following statements regarding reluctance-start motor is incorrect ? It is basically an induction motor and not a synchronous one the air-gap between rotor and salient poles is non- uniform It is similar to reluctance motor So far as its basic working principle is concerned, it is similar to shaded pole motor 7 / 50 The unit of retentivity is____________? ampere turn ampere turn/meter weber weber/sq. m 8 / 50 After the starting winding of a single phase induction motor is disconnected from supply, it continues to run only on ______________? running winding field winding rotor winding compensating winding 9 / 50 In a shaded pole motor, the shading coil usually consist of___________? a multilayer fine gauge copper wire in parallel with running winding a single turn of heavy copper wire which is short-circuited and carries only induced current a single turn of heavy wire which is in parallel with running winding none of the above 10 / 50 The efficiency of chimney is approximately______________? 80% 20% 0.25% 40% 11 / 50 When a step-input is given to an op-amp integrator, the output will be______________? A rectangular wave A ramp A sinusoidal wave A triangular wave with dc bias 12 / 50 A certain amount of current flows through a ring-shaped coil with fixed number of turns. How does the magnetic induction B varies inside the coil if an iron core is threaded into coil without dimensional change of coil ? Increases Decreases Remains same First increases and then decreases depending on the depth of iron in?sertion 13 / 50 In a Weston synchronoscope, the fixed coils are connected across_______________? incoming alternator bus-bars none of the above a lamp 14 / 50 The degree of mechanical vibrations produced by the laminations of a transformer depends on____________? size of laminations tightness of clamping gauge of laminations all of the above 15 / 50 When a wave propagates on a transmission line, it suffers reflection several times at_____________? sending and other end sending end load end tapping 16 / 50 The laminations of the armature of a D.C. machine are usually ___________ thick? 0.3 to 0.4 mm 0.1 to 0.2 mm 0.4 to 0.5 mm 0.2 to 0.3 mm 17 / 50 A certain common-source JFET has a voltage gain of 10. If the source bypass capacitor is removed, ______________? the voltage gain will increase the transconductance will increase the voltage gain will decrease the Q-point will shift 18 / 50 Sparking at the commutator of a D.C. motor may result in____________? damage to commutator insulation all of the above increased power consumption damage to commutator segments 19 / 50 A squirrel cage induction motor is not selected when___________? maintenance cost is to be kept low initial cost is the main consideration all above considerations are involved higher starting torque is the main consideration 20 / 50 Yokes with rectangular cross-section are used for_______________? medium capacity transformers any of the above small capacity transformers large capacity transformers 21 / 50 In open loop system_____________? the control action depends on the input signal the control action depends on the size of the system the control action depends on system variables the control action is independent of the output 22 / 50 310 km line is considered as_______________? a medium line any of the above a long line a short line 23 / 50 Which of the following are integrating instruments ? Ampere-hour and watt-hour meters Wattmeters Ammeters Voltmeters 24 / 50 If a power cable and a communication cable are to run parallel the minimum distance between the two, to avoid interference, should be______________? 50 cm 2 cm 400 cm 10 cm 25 / 50 In a rotary converter armature currents are______________? None partly a.c. and partly d.c. d.c. only a.c. only 26 / 50 The current zero interruption, in oil and air blast circuit breakers, is achieved by____________? cooling and blast effect lengthening of the gap deionizing the oil with forced air both (A) and (B) 27 / 50 Current produced by moving the loop of wire across a magnetic field is called_____________? mean square current A.C current induced current D.C current 28 / 50 An ideal regulated power supply is one which has voltage regulation of________________? 0% 10% 5% 1% 29 / 50 Two transformers are connected in parallel. These transformers do not have equal percentage impedance. This is likely to result in____________? loading of the transformers not in proportion to their kVA ratings short-circuiting of the secondaries power factor of one of the transformers is leading while that of the other lagging transformers having higher copper losses will have negligible core losses 30 / 50 The time constant of an R-C circuit is defined as the time during which capacitor charging voltage actually rises to _________ percent of its value 37, initial 62, initial 37, final 62, final 31 / 50 The angle between the rotating stator flux and rotor poles is called _________ angle. obtuse power factor torque synchronizing 32 / 50 Most of the majority carriers from the emitter____________? none of the above recombine in the emitter pass through the base region to the collector recombine in the base 33 / 50 n a phase controlled 3 phase ac voltage controller, the harmonic present is__________? 2nd 5th 7th 3rd 34 / 50 Which of the following is an advantage of static capacitor for power factor improvement? All of the above Low losses Ease in installation Little maintenance cost 35 / 50 Which of the following statements is correct for a system with gain margin close to unity or a phase margin close to zero ? The system is highly stable The system is relatively stable None of the above The system is highly oscillatory 36 / 50 Transistor biasing represents ______________ conditions? both a.c. and d.c a.c none of the above d.c 37 / 50 The phase angle of gate signal in TRIAC can be shifted by using_____________? A capacitor A variable resistor An inductor Only (a) and (b) 38 / 50 If the maximum collector current due to signal alone is 3 mA, then zero signal collector current should be at least equal to___________________? mA 6 mA 1 mA 3 mA 39 / 50 As a result of introduction of negative feedback which of the following will not decrease ? Overall gain Distortion Band width Instability 40 / 50 A gas turbine basically work on Rankin cycle Brayton cycle Carnot cycle Dual cycle 41 / 50 The above statement is associated with compensation theorem reciprocity theorem none of the above superposition theorem 42 / 50 If load resistance in the above question (Q.49) is removed, the output voltage will_____________? stay the same be zero decrease increase 43 / 50 For intermittent work which of the following furnaces is suitable ? Indirect arc furnace Core less furnace Either of the above None of the above 44 / 50 In Colpitt?s oscillator, feedback is obtained___________? By magnetic induction From the centre of split capacitors By a tickler coil None of the above 45 / 50 In an AC. circuit, a low value of kVAR compared with kW indicates_________? unity power factor maximum load current low efficiency high power factor 46 / 50 When the load resistance equals the generator resistance which of the following will be maximum __________? Power in the load resistance Voltage across the load resistance Current Efficiency of the circuit 47 / 50 The voltage drop for which of the following types of brush can be expected to be least ? Metal graphite brushes Carbon brushes Graphite brushes None of the above 48 / 50 If three 15 uF capacitors are connected in series, the net capacitance is 45 uF 50 uF 30 uF 5 uF 49 / 50 In order to remove static electricity from machinery___________? insulate the machinery construct insulated cabins humidify the surroundings ground the framework 50 / 50 Capacitance increases with_____________? increase in plate area and distance between the plates increase in plate area and decrease in distance between the plates reduction in plate area and distance between the plates decrease in plate area and value of applied voltage Provide Your Information Your score is The average score is 0% LinkedIn Facebook Twitter 0% Restart quiz Send feedback Share on facebook Facebook Share on twitter Twitter Share on whatsapp WhatsApp PrevElectrical Engineering Quiz 7 Electrical Engineering Quiz 9Next
