McqMate
| 1. |
Moving Iron instruments can be used on: |
| A. | ac and dc both |
| B. | ac only |
| C. | dc only |
| D. | none of the above |
| Answer» A. ac and dc both | |
| 2. |
In spring control instruments, controlling torque: |
| A. | can be adjusted easily |
| B. | cannot be adjusted easily |
| C. | remains the same |
| D. | varies with the load |
| Answer» B. cannot be adjusted easily | |
| 3. |
Chemical effect is used for the operation of: |
| A. | voltmeter |
| B. | ammeter |
| C. | ampere hour meter |
| D. | kwh meter |
| Answer» C. ampere hour meter | |
| 4. |
The deflection torque can be produced by: |
| A. | gravity control |
| B. | spring control |
| C. | air friction |
| D. | magneitcally |
| Answer» D. magneitcally | |
| 5. |
Moving coil instruments are: |
| A. | permanent magnet type |
| B. | dynamometer type |
| C. | induction type |
| D. | permanent magnet and dynamometer type |
| Answer» D. permanent magnet and dynamometer type | |
| 6. |
For increasing the range of an ammeter, connect: |
| A. | a high value resistance in series with the ammeter coil |
| B. | a high value resistance in parallel with the ammeter coil |
| C. | a low value resistance in parallel with the ammeter coil |
| D. | a low value resistance in series with the ammeter coil |
| Answer» C. a low value resistance in parallel with the ammeter coil | |
| 7. |
A galvanometer can be used for measuring current and voltage of a circuit by: |
| A. | shunt only |
| B. | connecting high value of resistance in series only |
| C. | shunt for measuring current and high resistance in series for voltage |
| D. | without shunt and series resistance |
| Answer» C. shunt for measuring current and high resistance in series for voltage | |
| 8. |
The energy consumption of MI instrument as compared to MC instrument is: |
| A. | same |
| B. | more |
| C. | less |
| D. | very small |
| Answer» B. more | |
| 9. |
An ammeter requires a change of 4A in its coil to produce a pointer deflection of 8mm then its sensitivity is |
| A. | 2.5 mm/a |
| B. | 2.0 mm/a |
| C. | 0.5 mm/a |
| D. | none of the above |
| Answer» B. 2.0 mm/a | |
| 10. |
Electrostatic type instruments are mainly used for measurement of |
| A. | heavy currents |
| B. | low currents |
| C. | low voltages |
| D. | high voltages |
| Answer» D. high voltages | |
| 11. |
Measurement range of a voltmeter can be extended by using: |
| A. | high current resistance |
| B. | high series resistance |
| C. | low shunt resistance |
| D. | low series resistance |
| Answer» B. high series resistance | |
| 12. |
Which of the following voltmeter have least power consumption: |
| A. | moving iron |
| B. | hot-wire |
| C. | electrostatic |
| D. | induction type |
| Answer» C. electrostatic | |
| 13. |
Which of the following instruments have least torque/weight ratio: |
| A. | dynamometer type |
| B. | pmmc |
| C. | attraction type moving iron |
| D. | repulsion type moving iron |
| Answer» A. dynamometer type | |
| 14. |
Fluid friction damping can be used in |
| A. | horizontally mounted instruments |
| B. | vertically mounted instruments |
| C. | both horizontally mounted instruments and vertically mounted instruments |
| D. | none of the above |
| Answer» B. vertically mounted instruments | |
| 15. |
The ratio and phase angle errors in potential transformer may be reduced by |
| A. | increasing the exciting current |
| B. | increasing the resistance and leakage reactance in the transformer |
| C. | by not employing turns compensation |
| D. | none of the above |
| Answer» D. none of the above | |
| 16. |
A voltmeter should have |
| A. | . low internal resistance |
| B. | . high internal resistance |
| C. | . electrostatic plates |
| D. | . a sensitive amplifier |
| Answer» B. . high internal resistance | |
| 17. |
The major advantage of electromagnet type meter over a permanent magnet meter is |
| A. | . the electromagnet meter costs much less |
| B. | the permanent magnet meter has a more sluggish coil |
| C. | . the electromagnet meter need not be aligned with the earth’s magnetic field |
| D. | . the electromagnet meter is more rugged |
| Answer» D. . the electromagnet meter is more rugged | |
| 18. |
The change in the direction of a compass needle, when a current carrying wire is brought near, is called |
| A. | . electromagnetic deflection |
| B. | . electroscopic force |
| C. | magnetic force |
| D. | . electrostatic force |
| Answer» A. . electromagnetic deflection | |
| 19. |
The use of _____ instruments is merely confined within laboratories as standardizing instruments. |
| A. | absolute |
| B. | indicating |
| C. | recording |
| D. | integrating |
| Answer» A. absolute | |
| 20. |
Which of the following instruments indicate the instantaneous value of the electrical quantity being measured at the time at which it is being measured ? |
| A. | absolute instruments |
| B. | indicating instruments |
| C. | recording instruments |
| D. | integrating instruments |
| Answer» B. indicating instruments | |
| 21. |
_____ instruments are those which measure the total quantity of electricity delivered in a particular time. |
| A. | absolute |
| B. | indicating |
| C. | recording |
| D. | integrating |
| Answer» D. integrating | |
| 22. |
Which of the following are integrating instruments ? |
| A. | ammeters |
| B. | voltmeters |
| C. | wattmeters |
| D. | ampere-hour and watt-hour meters |
| Answer» D. ampere-hour and watt-hour meters | |
| 23. |
Which of the following essential features is possessed by an indicating instrument ? |
| A. | deflecting device |
| B. | controlling device |
| C. | damping device |
| D. | all of the above |
| Answer» D. all of the above | |
| 24. |
A _____ device prevents the oscillation of the moving system and enables the latter to reach its final position quickly |
| A. | deflecting |
| B. | controlling |
| C. | damping |
| D. | any of the above |
| Answer» C. damping | |
| 25. |
The spring material used in a spring control device should have the following property. |
| A. | should be non-magnetic |
| B. | most be of low temperature co-efficient |
| C. | should have low specific resistance |
| D. | all of the above |
| Answer» D. all of the above | |
| 26. |
Which of the following properties a damping oil must possess ? |
| A. | must be a good insulator |
| B. | should not have corrosive action upon the metal of the vane |
| C. | the viscosity of the oil should not change with the temperature |
| D. | all of the above |
| Answer» D. all of the above | |
| 27. |
Which of the following devices may be used for extending the range of instruments ? |
| A. | shunts |
| B. | multipliers |
| C. | current transformers |
| D. | all of the above |
| Answer» D. all of the above | |
| 28. |
For handling greater currents induction wattmeters are used in conjunction with |
| A. | potential transformers |
| B. | current transformers |
| C. | power transformers |
| D. | either of the above |
| Answer» B. current transformers | |
| 29. |
The pointer of an indicating instrument should be |
| A. | very light |
| B. | very heavy |
| C. | either (a) or (b) |
| D. | neither (a) nor (b) |
| Answer» A. very light | |
| 30. |
In majority of instruments damping is provided by |
| A. | fluid friction |
| B. | spring |
| C. | eddy currents |
| D. | all of the above |
| Answer» C. eddy currents | |
| 31. |
An ammeter is a |
| A. | secondary instrument |
| B. | absolute instrument |
| C. | recording instrument |
| D. | integrating instrument |
| Answer» A. secondary instrument | |
| 32. |
In a portable instrument, the controlling torque is provided by |
| A. | spring |
| B. | gravity |
| C. | eddy currents |
| D. | all of the above |
| Answer» A. spring | |
| 33. |
The desirable static characteristics of a measuring system are |
| A. | accuracy and reproducibility |
| B. | accuracy, sensitivity and reproducibility |
| C. | drift and dead zone |
| D. | static error |
| Answer» B. accuracy, sensitivity and reproducibility | |
| 34. |
The ratio of maximum displacement deviation to full scale deviation of the instrument is called |
| A. | static sensitivity |
| B. | dynamic deviation |
| C. | linearity |
| D. | precision or accuracy |
| Answer» C. linearity | |
| 35. |
Systematic errors are |
| A. | instrumental errors |
| B. | environmental errors |
| C. | observational errors |
| D. | all of the above |
| Answer» D. all of the above | |
| 36. |
The gravity controlled instrument has crowded scale because current is proportional to |
| A. | balancing weight |
| B. | deflection angle |
| C. | sine of deflection angle |
| D. | none of the above |
| Answer» C. sine of deflection angle | |
| 37. |
Instrument transformers are |
| A. | potential transformers |
| B. | current transformers |
| C. | both (a) and (b) |
| D. | power transformers |
| Answer» C. both (a) and (b) | |
| 38. |
The damping force acts on the moving system of an indicating instruments only when it is |
| A. | moving |
| B. | stationary |
| C. | near its full scale deflection |
| D. | just staring to move |
| Answer» A. moving | |
| 39. |
A moving iron ammeter coil has few turns of thick wire in order to have: |
| A. | high sensitivity |
| B. | effective damping |
| C. | low resistance and large current carrying capacity |
| D. | large scale |
| Answer» C. low resistance and large current carrying capacity | |
| 40. |
Swamping of resistance is used to compensate error due to: |
| A. | stray magnetic field |
| B. | temperature variations |
| C. | large supply variations |
| D. | none of the above |
| Answer» B. temperature variations | |
| 41. |
The turns ratio for C.T. is defined as |
| A. | n2/n1 |
| B. | n1/n2 |
| C. | (n1+n2)/n1 |
| D. | (n1+n2)/n2 |
| Answer» A. n2/n1 | |
| 42. |
A 3810/63 P.T. is used with a voltmeter gives reading of 28.11 V , then the actual line voltage is ------ V |
| A. | 0.4648 |
| B. | 975 |
| C. | 1700 |
| D. | 1100 |
| Answer» C. 1700 | |
| 43. |
A 1000:5 C.T. is used with an ammeter. If ammeter reading is 1.8 A then the actual line current is --------------A |
| A. | 160 |
| B. | 400 |
| C. | 0.09 |
| D. | 360 |
| Answer» D. 360 | |
| 44. |
While testing cables the galvanometer used should be initially short-circuited in order to protect it from sudden initial inrush currents as the cable have: |
| A. | a low value of initial resistance |
| B. | a low value of initial capacitance |
| C. | a high value of initial capacitance |
| D. | both (a) and (b) |
| Answer» C. a high value of initial capacitance | |
| 45. |
A megger indicates infinity when test terminals are open-circuited. This is because: |
| A. | no current flows through the current coil |
| B. | no current flows through the pressure coil |
| C. | no current flows through the compensating winding |
| D. | current does not flow through current coil and pressure coil |
| Answer» A. no current flows through the current coil | |
| 46. |
Potentiometer is an __ instrument: |
| A. | indicating |
| B. | comparison |
| C. | calibrating |
| D. | recording |
| Answer» B. comparison | |
| 47. |
Which of the following bridge is frequency sensitive: |
| A. | wheatstone bridge |
| B. | maxwell bridge |
| C. | anderson bridge |
| D. | wien bridge |
| Answer» C. anderson bridge | |
| 48. |
The size of the earth or ground wire is based on the: |
| A. | maximum fault current carrying through the ground wire |
| B. | rated current carrying capacity of the service line |
| C. | depends on the soil resistance |
| D. | both (a) and (c) |
| Answer» D. both (a) and (c) | |
| 49. |
Earth wire or ground wire is made of: |
| A. | copper |
| B. | aluminium |
| C. | iron |
| D. | galvanized steel |
| Answer» D. galvanized steel | |
| 50. |
Average resistance of human body is: |
| A. | 500 ohms |
| B. | 1000 ohms |
| C. | 1500 ohms |
| D. | 2000 ohms |
| Answer» B. 1000 ohms | |
| 51. |
Generally grounding is provided for: |
| A. | only for the safety of the equipment |
| B. | only for the safety of the operating personnel |
| C. | both (a) and (b) |
| D. | none of the above |
| Answer» C. both (a) and (b) | |
| 52. |
Ground resistance should be designed such that: |
| A. | grounding resistance should be as low as possible |
| B. | grounding resistance should be as high as possible |
| C. | grounding resistance should be always zero |
| D. | none of the above |
| Answer» A. grounding resistance should be as low as possible | |
| 53. |
The objective of earthing or grounding is: |
| A. | to provide as low resistance possible to the ground |
| B. | to provide as high resistance possible to the ground |
| C. | to provide flow of positive, negative and zero sequence currents |
| D. | none of the above |
| Answer» A. to provide as low resistance possible to the ground | |
| 54. |
The vale of resistance of an earthing electrode depends upon |
| A. | shape and material of the electrode |
| B. | depth to which electrode is driven into earth |
| C. | specific resistance of soil |
| D. | all of the above. |
| Answer» D. all of the above. | |
| 55. |
A bridge circuit works at a frequency of 2KHz, the following can be used as detectors for detection of null conditions in the bridge: |
| A. | vibration galvanometers and headphones |
| B. | headphones and tunable amplifiers. |
| C. | vibration galvanometers and tunable amplifiers. |
| D. | vibration galvanometers, headphones and tunable amplifiers. |
| Answer» B. headphones and tunable amplifiers. | |
| 56. |
Maxwell’s inductance capacitance bridge is used for measurement of inductance of: |
| A. | low q coils |
| B. | medium q coils |
| C. | low and medium q coils |
| D. | none of the above. |
| Answer» B. medium q coils | |
| 57. |
The wheatstone bridge cant be used for precision measurements because errors are introduce into on account of : |
| A. | resistance of connecting leads |
| B. | thermo electric emf |
| C. | contact resistances |
| D. | all of the above. |
| Answer» D. all of the above. | |
| 58. |
High resistances are provided with a guard terminal. This guard terminal is used to : |
| A. | bypass leakage current |
| B. | guard the resistance against stray electrostatic fields |
| C. | guard the resistance against over loads. |
| D. | none of the above. |
| Answer» A. bypass leakage current | |
| 59. |
A potentiometer may be used for |
| A. | measurement of resistance |
| B. | measurement of current |
| C. | calibration of voltmeter |
| D. | all of the above |
| Answer» D. all of the above | |
| 60. |
--------- is an instrument which measures the insulation resistance of an electric circuit relative to earth and one another, |
| A. | tangent galvanometer |
| B. | meggar |
| C. | current transformer |
| D. | none of the above |
| Answer» B. meggar | |
| 61. |
For measuring a very high resistance we should use |
| A. | kelvin\s double bridge |
| B. | wheat stone bridge |
| C. | meggar |
| D. | none of the above |
| Answer» C. meggar | |
| 62. |
The electrical power to a meggar is provided by |
| A. | battery |
| B. | permanent magnet d.c. generator |
| C. | ac. generator |
| D. | any of the above |
| Answer» B. permanent magnet d.c. generator | |
| 63. |
In a meggar controlling torque is provided by |
| A. | spring |
| B. | gravity |
| C. | coil |
| D. | eddy current |
| Answer» C. coil | |
| 64. |
The operating voltage of a meggar is about |
| A. | 6 v |
| B. | 12 v |
| C. | 40 v |
| D. | 100 v |
| Answer» D. 100 v | |
| 65. |
Which of the following devices should be used for accurate measurement of low D.C. voltage ? |
| A. | small range moving coil voltmeter |
| B. | d.c. potentiometer |
| C. | small range thermocouple voltmeter |
| D. | none of the above |
| Answer» B. d.c. potentiometer | |
| 66. |
It is required to measure the true open circuit e.m.f. of a battery. The best device is |
| A. | d.c. voltmeter |
| B. | ammeter and a known resistance |
| C. | d.c. potentiometer |
| D. | none of the above |
| Answer» C. d.c. potentiometer | |
| 67. |
In an Anderson bridge, the unknown inductance is measured in terms of |
| A. | known inductance and resistance |
| B. | known capacitance and resistance |
| C. | known resistance |
| D. | known inductance |
| Answer» B. known capacitance and resistance | |
| 68. |
If the current in a capacitor leads the voltage by 80°, the loss angle of the capacitor is |
| A. | 10° |
| B. | 80° |
| C. | 120° |
| D. | 170° |
| Answer» A. 10° | |
| 69. |
To avoid the effect of stray magnetic field in A.C. bridges we can use |
| A. | magnetic screening |
| B. | wagner earthing device |
| C. | wave filters |
| D. | any of the above |
| Answer» A. magnetic screening | |
| 70. |
Standard resistor is made from |
| A. | platinum |
| B. | maganin |
| C. | silver |
| D. | nichrome |
| Answer» B. maganin | |
| 71. |
Commonly used standard capacitor is |
| A. | spherical type |
| B. | concentric cylindrical type |
| C. | electrostatic type |
| D. | multilayer parallel plate type |
| Answer» B. concentric cylindrical type | |
| 72. |
The most commonly used null deflector in a power frequency ac bridge is a |
| A. | vibration galvanometer |
| B. | d\arsanval galvanometer |
| C. | ballistic galvanometer |
| D. | tachometer |
| Answer» A. vibration galvanometer | |
| 73. |
Loss of charge method is used to measure: |
| A. | low r |
| B. | high r |
| C. | low l |
| D. | high l |
| Answer» B. high r | |
| 74. |
Megger is an instrument used for the measurement of: |
| A. | high resistance and insulation resistance |
| B. | medium resistance |
| C. | low resistance |
| D. | leakage current |
| Answer» A. high resistance and insulation resistance | |
| 75. |
Anderson bridge is used to measure of: |
| A. | inductance |
| B. | capacitance |
| C. | time period |
| D. | resistance and capacitance |
| Answer» A. inductance | |
| 76. |
In an electro dynamometer type of wattmeter |
| A. | the current coil is made fixed |
| B. | the pressure coil is fixed |
| C. | any of the two coils current coil or pressure coil can be made fixed. |
| D. | both the coils should be movable. |
| Answer» A. the current coil is made fixed | |
| 77. |
In electro dynamometer type of wattmeter current coils designed for carrying heavy currents use stranded wires or laminated conductors : |
| A. | to reduce iron losses |
| B. | to reduce hysteresis losses |
| C. | to reduce eddy current losses in the conductors |
| D. | all of the above. |
| Answer» C. to reduce eddy current losses in the conductors | |
| 78. |
In an electro dynamometer type of wattmeter , the inductance of the pressure coil circuit produces error : |
| A. | which is constant irrespective of the power factor of the load |
| B. | which is higher at low power factors |
| C. | which is lower at low power factors |
| D. | none of the above. |
| Answer» B. which is higher at low power factors | |
| 79. |
The power in 3ph 4 wire circuit can be measured by using: |
| A. | five watt meters |
| B. | four watt meters |
| C. | three watt meters |
| D. | 1 watt meter. |
| Answer» C. three watt meters | |
| 80. |
The resistance in the circuit of the moving coil of a dynamometer wattmeter should be |
| A. | almost zero |
| B. | low |
| C. | high |
| D. | none of the above |
| Answer» C. high | |
| 81. |
A dynamometer wattmeter can be used for |
| A. | both d.c. and a.c. |
| B. | d.c. only |
| C. | a.c. only |
| D. | any of the above |
| Answer» A. both d.c. and a.c. | |
| 82. |
The pressure coil of a wattmeter should be connected on the supply side of the current coil when |
| A. | load impedance is high |
| B. | load impedance is low |
| C. | supply voltage is low |
| D. | none of the above |
| Answer» A. load impedance is high | |
| 83. |
In a low power factor wattmeter the pressure coil is connected |
| A. | to the supply side of the current coil |
| B. | to the load side of the current coil |
| C. | in any of the two meters at connection |
| D. | none of the above |
| Answer» B. to the load side of the current coil | |
| 84. |
In a low power factor wattmeter the compensating coil is connected |
| A. | in series with current coil |
| B. | in parallel with current coil |
| C. | in series with pressure coil |
| D. | in parallel with pressure coil |
| Answer» C. in series with pressure coil | |
| 85. |
In a dynamometer 3-phase power factor meter, the planes of the two moving coils are at |
| A. | 0° |
| B. | 60° |
| C. | 90° |
| D. | 120° |
| Answer» D. 120° | |
| 86. |
The power factor of a single phase load can be calculated if the instruments available are |
| A. | one voltmeter and one ammeter |
| B. | one voltmeter, one ammetqr and one wattmeter |
| C. | one voltmeter, one ammeter and one energy meter |
| D. | any of the above |
| Answer» B. one voltmeter, one ammetqr and one wattmeter | |
| 87. |
The power of a n-phase circuit can be measured by using a minimum of |
| A. | (n - 1) wattmeter elements |
| B. | n wattmeter elements |
| C. | (n + 1) wattmeter elements |
| D. | 2n wattmeter elements |
| Answer» A. (n - 1) wattmeter elements | |
| 88. |
A Dynamometer type wattmeter responds to the: |
| A. | average value of the active power |
| B. | average value of the reactive power |
| C. | peak value of the active power |
| D. | peak value of the reactive power |
| Answer» A. average value of the active power | |
| 89. |
The power measurement in a balanced 3-phase circuit can be done by: |
| A. | one wattmeter method |
| B. | two wattmeter method |
| C. | three wattmeter method |
| D. | any of the above method |
| Answer» D. any of the above method | |
| 90. |
The braking torque provided by a permanent magnet in a single phase energy meter is proportional to the |
| A. | square of the flux of the permanent magnet |
| B. | speed of the meter |
| C. | distance of the permanent magnet from the centre of the revolving disc |
| D. | all of the above. |
| Answer» D. all of the above. | |
| 91. |
Which of the following is integrating instruments? |
| A. | power factor meter |
| B. | energy meter |
| C. | voltmeter |
| D. | ammeter |
| Answer» B. energy meter | |
| 92. |
The phenomenon of creeping occurs in |
| A. | voltmeter |
| B. | ammeter |
| C. | wattmeter |
| D. | watt-hour meter |
| Answer» D. watt-hour meter | |
| 93. |
Hole s are drilled on the opposite sides of the spindle of an energy meter to avoid |
| A. | balance of the disc |
| B. | dissipate heat generated due to eddy currents |
| C. | avoid creep on load |
| D. | increase the deflection torque |
| Answer» C. avoid creep on load | |
| 94. |
The pressure coil of an induction type energy meter is |
| A. | highly inductive |
| B. | highly resistive |
| C. | purely inductive |
| D. | purely resistive |
| Answer» A. highly inductive | |
| 95. |
Which type of damping is used in Induction type energy meter? |
| A. | air friction |
| B. | fluid friction |
| C. | gravity |
| D. | eddycurrent |
| Answer» D. eddycurrent | |
| 96. |
In an Induction type energy meter, maximum torque is obtained when the parameter of the rotating disc are |
| A. | r=0 |
| B. | x=0 |
| C. | r=x |
| D. | none of the above |
| Answer» B. x=0 | |
| 97. |
An Induction meter meter can handle current upto |
| A. | 10a |
| B. | 30a |
| C. | 200a |
| D. | 100a |
| Answer» D. 100a | |
| 98. |
In an induction type energy meter, compensation for static friction is provided by |
| A. | drilling holes in the disc |
| B. | lag circuits |
| C. | shading bands |
| D. | none of the above |
| Answer» C. shading bands | |
| 99. |
Which of the following statements is wrong |
| A. | there is control spring |
| B. | there is a brake magnet |
| C. | creeping error is present |
| D. | disc revolves continuously |
| Answer» A. there is control spring | |
| 100. |
Which of the following is an essential part of a induction type of meter ? |
| A. | an operating torque system |
| B. | a braking device |
| C. | revolution registering device |
| D. | all of the above |
| Answer» D. all of the above | |
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