MCQOPTIONS
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MCQOPTIONS
This section includes 657 Mcqs, each offering curated multiple-choice questions to sharpen your Testing Subject knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
__A CRO can display__ |
| A. | AC signals |
| B. | DC signals |
| C. | Both AC and DC signals |
| D. | Time invariant signals |
| Answer» D. Time invariant signals | |
| 2. |
__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» B. Load impedance is low | |
| 3. |
__The absolute measurement of resistance is done by__ |
| A. | Ohm’s law method |
| B. | Bridge Method |
| C. | Rayleigh method |
| D. | Lorenz method |
| Answer» E. | |
| 4. |
__The current coil of a wattmeter is connected to the CT of R-phase. The potential coil is connected across Y and B phases. The wattmeter measures__ |
| A. | Active power in R phase |
| B. | Active power of Y phase |
| C. | Reactive power of R phase |
| D. | Power proportional to 3 phase power if the load is balanced |
| Answer» D. Power proportional to 3 phase power if the load is balanced | |
| 5. |
__The resistance can be measured most accurately by__ |
| A. | Voltmeter-ammeter method |
| B. | Bridge method |
| C. | Multimeter |
| D. | Megger |
| Answer» C. Multimeter | |
| 6. |
__The resistance offered to the passage of an in-varying current by a column of mercury at the temperature of melting ice of mass 14.4521 gms of uniform cross-sectional area and length 106.3cm is__ |
| A. | Standard ohm |
| B. | One international ohm |
| C. | One ohm according to SI units |
| D. | One ohm according to working standards |
| Answer» C. One ohm according to SI units | |
| 7. |
__Wagner earthing device is used to eliminate errors due to__ |
| A. | Electrostatic coupling |
| B. | Electromagnetic coupling |
| C. | Both A and B |
| D. | None of the above |
| Answer» B. Electromagnetic coupling | |
| 8. |
_Why is a MISC meter not recommended for DC measurement?$? |
| A. | The meter is calibrated for AC and it’s error for DC would be high |
| B. | The meter does not respond to DC signals |
| C. | The error is high due to hysteresis effect |
| D. | The error is high due to eddy current effect |
| Answer» D. The error is high due to eddy current effect | |
| 9. |
It can be stated that$? |
| A. | CT operates at almost the same flux density as a PT |
| B. | CT operates with a higher flux density than PT |
| C. | CT operates with considerably lower flux density than a PT |
| D. | No generalisation can be made with regard to the flux densities in CT and PT |
| Answer» D. No generalisation can be made with regard to the flux densities in CT and PT | |
| 10. |
PMMC type instruments normally use$? |
| A. | Air friction damping |
| B. | Fluid friction damping |
| C. | Eddy current damping |
| D. | None of the above |
| Answer» D. None of the above | |
| 11. |
Which of the following instruments can be used to measure AC current only?$? |
| A. | Permanent Magnet Type ammeter |
| B. | Induction type ammeter |
| C. | Moving iron voltmeter |
| D. | Moving iron ammeter |
| Answer» C. Moving iron voltmeter | |
| 12. |
Which of the following devices should be used for accurate measurement of low D.C. voltage?$? |
| A. | Small range moving coil voltmeter |
| B. | D.C. potentiometer |
| C. | Small range thermocouple voltmeter |
| D. | None of the above |
| Answer» C. Small range thermocouple voltmeter | |
| 13. |
Ampere is one of the$? |
| A. | Supplementary units |
| B. | Derived units |
| C. | Base units |
| D. | Units used to measure charge |
| Answer» D. Units used to measure charge | |
| 14. |
A 10MHz CRO has$? |
| A. | 5MHz sweep |
| B. | 10MHz vertical oscillator |
| C. | 10MHz horizontal oscillator |
| D. | 10MHz supply frequency |
| Answer» D. 10MHz supply frequency | |
| 15. |
Some wire- wound resistors have bifilar winding. This type of winding is used to$? |
| A. | Increase the thermal stability |
| B. | Reduce the tolerance |
| C. | Reduce the inductance of winding |
| D. | Double the power rating of the resistor |
| Answer» D. Double the power rating of the resistor | |
| 16. |
No eddy current and hysteresis losses occur in$? |
| A. | Electrostatic instruments |
| B. | PMMC instruments |
| C. | Moving iron instruments |
| D. | Electrodynamo meter instruments |
| Answer» B. PMMC instruments | |
| 17. |
Which wave has the least form factor?$? |
| A. | Square wave |
| B. | Rectangular wave |
| C. | Sine wave |
| D. | Triangular wave |
| Answer» B. Rectangular wave | |
| 18. |
Direct method is used to measure$? |
| A. | Length |
| B. | Temperature |
| C. | Pressure |
| D. | Voltage |
| Answer» B. Temperature | |
| 19. |
The repeat accuracy of an instrument can be judged from its$? |
| A. | Static error |
| B. | Linearity error |
| C. | Dynamic error |
| D. | Standard deviation of error |
| Answer» E. | |
| 20. |
A mulliammeter can be used as$? |
| A. | Voltmeter and ammeter |
| B. | Wattmeter |
| C. | Ohmmeter |
| D. | Frequency meter |
| Answer» B. Wattmeter | |
| 21. |
The spring material used in a spring control device should have the following property.? |
| A. | Should be nonmagnetic |
| B. | Most be of low temperature coefficient |
| C. | Should have low specific resistance |
| D. | All of the above |
| Answer» E. | |
| 22. |
If the instrument is to have a wide range, the instrument should have |
| A. | Linear scale |
| B. | Square-law scale |
| C. | Exponential scale |
| D. | Logarithmic scale |
| Answer» E. | |
| 23. |
A spring controlled indicating instrument has a deflection of 90deg for maximum current I. The corresponding deflection for a gravity controlled instrument is |
| A. | 90° |
| B. | 120° |
| C. | 30° |
| D. | 0° |
| Answer» D. 0¬¨‚àû | |
| 24. |
The thermocouple instruments do not have |
| A. | High sensitivity |
| B. | Absence of frequency error |
| C. | Independence of ambient temperature |
| D. | High degree of measuring accuracy |
| Answer» E. | |
| 25. |
Which meter is suitable for the measurement of 10mV at 50MHz? |
| A. | Moving iron voltmeter |
| B. | VTVM |
| C. | Moving coil voltmeter |
| D. | CRO |
| Answer» E. | |
| 26. |
When using ohmmeter, applied voltage is to be disconnected from the circuit because |
| A. | Voltage source will increase resistance |
| B. | Current will decrease resistance |
| C. | The ohmmeter has its own internal battery |
| D. | None of the above |
| Answer» D. None of the above | |
| 27. |
To measure the flux, devices used are based on |
| A. | Voltaic effect |
| B. | Piezo-electric effect |
| C. | Hall effect |
| D. | Photo-voltaic effect |
| Answer» D. Photo-voltaic effect | |
| 28. |
In a moving iron meter, the deflecting torque is proportional to |
| A. | Current through the coil |
| B. | Square of the current through the coil |
| C. | Sine of the measurand |
| D. | Squareroot of the measurand |
| Answer» C. Sine of the measurand | |
| 29. |
Ryall crest voltmeter is used for measurement of |
| A. | AC voltage of any form |
| B. | Low frequency voltage |
| C. | High DC voltage |
| D. | High AC voltage |
| Answer» E. | |
| 30. |
The error of an instrument is normally given as a percentage of |
| A. | Measured value |
| B. | Full-scale value |
| C. | Mean value |
| D. | Rms value |
| Answer» C. Mean value | |
| 31. |
The EMF of Weston standard cell is measured using |
| A. | Moving- iron meter |
| B. | Moving-coil meter |
| C. | Digital Volt meter |
| D. | Potentiometer |
| Answer» E. | |
| 32. |
One single phase wattmeter operating on 230V and 5A for 5 hours makes 1940 revolutions. Meter constant in revolutions is 400. What is the power factor of the land? |
| A. | 1 |
| B. | 0.84 |
| C. | 0.73 |
| D. | 0.65 |
| Answer» C. 0.73 | |
| 33. |
The full-scale deflection current of an ammeter is 1 mA and its internal resistance is 100°hm. If this meter is to have full deflection at 5A, what is the value of the shunt resistance to be used?# |
| A. | 49.99 Ohms |
| B. | 1/49.99 ohms |
| C. | 1 Ohm |
| D. | 2 Ohms |
| Answer» C. 1 Ohm | |
| 34. |
The full-scale deflection current of an ammeter is 1 mA and its internal resistance is 100°hm. This is to have full deflection when 100V is measured. What is the value of series resistor to be used?# |
| A. | 99.99 K ohms |
| B. | 100 K ohms |
| C. | 99.99 ohms |
| D. | 100 ohms |
| Answer» B. 100 K ohms | |
| 35. |
The thermocouple instrument will measure |
| A. | Current |
| B. | Voltage |
| C. | Flux |
| D. | None of the above |
| Answer» E. | |
| 36. |
The problem of Electrostatic coupling in a transformer is acute at |
| A. | Low frequencies |
| B. | Power frequencies |
| C. | High frequencies |
| D. | High load on the transformer |
| Answer» D. High load on the transformer | |
| 37. |
A megger is usually |
| A. | Moving iron type instrument |
| B. | Electro-static type instrument |
| C. | Hot-wire type instrument |
| D. | Moving coil type instrument |
| Answer» E. | |
| 38. |
For handling greater currents induction watt-meters are used in conjunction with |
| A. | Potential transformers |
| B. | Current transformers |
| C. | Power transformers |
| D. | Either of the above |
| Answer» C. Power transformers | |
| 39. |
A permanent magnet moving coil ammeter has a coil resistance of 99ohm and Full Scale DeflectionFSD. current of 0.1mA. Shunt resistance is 1 ohm. Current through the meter at 0.5 F.S.D is |
| A. | 0.007mA |
| B. | 0.05mA |
| C. | 0.023mA |
| D. | 0.1mA |
| Answer» C. 0.023mA | |
| 40. |
The two pressure coils of a single phase power factor meter have |
| A. | The same dimensions and the same number of turns |
| B. | The same dimension but different number of turns |
| C. | The same number of turns but different dimensions |
| D. | None of the above |
| Answer» B. The same dimension but different number of turns | |
| 41. |
In a moving coil instrument, the deflecting torque is proportional to |
| A. | Current |
| B. | Square of the current |
| C. | Squareroot of the current |
| D. | Sine of the measurand |
| Answer» B. Square of the current | |
| 42. |
An oscilloscope indicates |
| A. | Peak to peak value of voltage |
| B. | DC value of voltage |
| C. | RMS value |
| D. | Average value |
| Answer» B. DC value of voltage | |
| 43. |
The form factor in AC is the ratio of |
| A. | Peak value to average value |
| B. | Peak value to rms value |
| C. | Rms value to average value |
| D. | Rms value to peak value |
| Answer» D. Rms value to peak value | |
| 44. |
It is found that 10A current passes through a resistor of 10°hms. The resistor has 5% tolerance . The error in measurement of current can be as high as 5%. What is max error in measurement of power, calculated from measured value of I and the nominal value of resistor?# |
| A. | 100W |
| B. | 150W |
| C. | 50W |
| D. | 200W |
| Answer» C. 50W | |