Electrical Measurement And Instrumentation MCQ

Electrical Measurement And Instrumentation MCQ

1)   Considering cost of instruments, which is better choice, active or passive?

a. Active instruments
b. Passive instruments
c. Cost of both active and passive instruments are approximately same
d. None of these

ANSWER: Passive instruments

2)   In deadweight gauge, weights are added on the top of piston until the piston reaches a datum level. The datum level is known as

a. Null point, where the downward force balances the fluid pressure
b. Lowest point of the container
c. Highest level of fluid in the container
d. None of these

ANSWER: Null point, where the downward force balances the fluid pressure

3)   The accuracy of the deflection type instruments and of the null type instruments depends on

a. Linearity, calibration of spring
b. Calibration of spring, linearity and calibration of weights
c. Linearity and calibration of spring, calibration of weights
d. Both depends on calibration of weight

ANSWER: Linearity and calibration of spring, calibration of weights

4)   In terms of usage, deflection type instruments are

a. More convenient than null type instrument
b. Less convenient than null type instruments
c. Both are equally convenient
d. None of these

ANSWER: More convenient than null type instrument

5)   The output of an analogue instrument varies

a. Continuously and can have an infinite number of values within its range of instruments
b. In discrete steps and can have an infinite number of values within its range of instruments
c. Continuously and can have an finite number of values within its range of instruments
d. In discrete steps and can have an infinite number of values within its range of instruments

ANSWER: Continuously and can have an infinite number of values within its range of instruments

Electrical Measurement And Instrumentation MCQ

6)   To read and record a measurement, the indicating type instruments

a. Always requires human intervention
b. Does not requires human intervention
c. Requires human intervention only when the instrument consists of a rotating pointer moving against a scale
d. Requires human intervention only when the instrument consists of a rotating scale moving against a pointer

ANSWER: Always requires human intervention

7)   The electromagnetic effect is generally utilized for

a. Ammeters
b. Voltmeters
c. Wattmeters and watt – hour meters
d. All of these

ANSWER: All of these

8)   The electrostatic effect is utilized for

a. Ammeters
b. Voltmeters
c. D.C. ampere – hour meters
d. Wattmeters

ANSWER: Voltmeters

9)   The instrument which can be used only with the D.C. supply is

a. PMMC instrument
b. Electrodynamometer instrument
c. Hot – wire instrument
d. Split phase induction type instrument

ANSWER: PMMC instrument

10)   The instrument which can be used only with the A.C. supply is / are

a. Induction type
b. Electrostatic type
c. Electrodynamometer type
d. All of these

ANSWER: Induction type

Electrical Measurement And Instrumentation MCQ

11)   In a hot wire ammeter the current flowing through the resistance of 10 Ω is given by
I = 3 + 2 sin 300 t A
The measured value of current will be

a. 2.98 A
b. 3.31 A
c. 3.62 A
d. 4.01 A

ANSWER: 3.31 A

12)   In a hot wire instrument, readings are

a. Dependent on frequency
b. Dependent on waveform
c. Dependent on both frequency and waveform
d. Independent of both frequency and waveform

ANSWER: Independent of both frequency and waveform

13)   To convert a 2 mA meter with internal resistance of 120 ohm into an ammeter of range 0 – 200 mA, the value of shunt resistance required is

a. 1.121 ohm
b. 1.212 ohm
c. 1.312 ohm
d. 1.414 ohm

ANSWER: 1.212 ohm

14)   If a moving iron instrument is to be used as ammeter then the coil has

a. Fewer number of turns of thin wire
b. Fewer number of turns of thick wire
c. Larger number of turns of thin wire
d. Larger number of turns of thick wire

ANSWER: Fewer number of turns of thick wire

15)   If the direction of current through the coil is upward, then the iron disc will be magnetized in such a way that it is

a. Pushed outwards
b. Pushed upwards
c. Pushed downwards
d. Pulled inwards

ANSWER: Pulled inwards

Electrical Measurement And Instrumentation MCQ

16)   In the given options, the secondary fundamental unit is

a. Length
b. Luminous intensity
c. Plane angle
d. Time

ANSWER: Luminous intensity

17)   Bridge circuits are used for the measurement of

a. Resistance
b. Inductance
c. Capacitance
d. All of these

ANSWER: All of these

18)   Low resistance is the resistance of the order of

a. 1 ohm and less than 1 ohm
b. 1 ohm to 1 mega ohm
c. More than one ohm
d. None of these

ANSWER: 1 ohm and less than 1 ohm

19)   The example of low resistance is / are

a. Resistance of armature windings of electrical machine
b. Resistance of series field winding of a dc machine
c. Resistances of shunts and lead wires
d. All of these

ANSWER: All of these

Electrical Measurement And Instrumentation MCQ

20)   AC bridges are used for the measurement of

a. Resistances
b. Resistances and Inductances
c. Inductances and capacitances
d. Resistances, inductances and capacitances

ANSWER: Inductances and capacitances

21)   The commonly used detector(s) in AC bridges is / arE

a. Head phones
b. Vibration galvanometers
c. Tuned amplifiers, head phones
d. Head phones, tuned amplifiers, vibration galvanometers

ANSWER: Head phones, tuned amplifiers, vibration galvanometers

22)   The vibration galvanometers are sensitive to power for frequency range of

a. 200 Hz and below
b. 200 Hz to about 4 kHz
c. 4 kHz and above
d. Any frequency

ANSWER: 200 Hz and below

23)   In case of DC supply and AC supply, the torque produced is

a. Directly proportional to power, inversely power to power
b. Directly proportional to power, directly proportional to power
c. Inversely proportional to power, inversely proportional to power
d. Inversely proportional to power, directly proportional to power

ANSWER: Directly proportional to power, directly proportional to power

24)   The scale of dynamometer wattmeter is

a. Approximately uniform
b. Cramped at the middle
c. Cramped at the end points
d. Crowded in the first half

ANSWER: Approximately uniform

Electrical Measurement And Instrumentation MCQ

25)   In standard wattmeters, the error caused by the voltage coil is overcome by

a. Connecting a high inductive resistance in series to the voltage coil
b. Connecting a high inductive resistance in parallel to the voltage coil
c. Connecting a compensating winding in series to the voltage coil
d. Connecting a compensating winding in parallel to the voltage coil

ANSWER: Connecting a compensating winding in series to the voltage coil

26)   In a dynamometer type wattmeter, the pressure coil connected across the load terminal is

a. Highly inductive
b. Highly capacitive
c. Highly resistive
d. Non inductive

ANSWER: Highly resistive

27)   The instrument which works only with DC is

a. Electrolytic motor
b. Mercury motor
c. Induction motor
d. Both (a) and (b)
e. None of these

ANSWER: Both (a) and (b)

28)   The electrolytic energy meters are essentially

a. A true watt – hour meter
b. An ampere hour meter
c. Either watt – hour or ampere hour meter
d. Neither watt – hour nor ampere hour meter

ANSWER: An ampere hour meter

29)   CRO gives the visual representation of time varying signals. The display of the signal is

a. One dimensional
b. Two dimensional
c. Three dimensional
d. Four dimensional

ANSWER: Two dimensional

30)   Principally CRO is a

a. Ammeter
b. Voltmeter
c. Wattmeter
d. Watt – hour meter

ANSWER: Voltmeter

Electrical Measurement And Instrumentation MCQ

31)   The sweep generator of a CRO is used to produce

a. Sinusoidal voltage for the horizontal deflection of electron beam
b. Saw tooth voltage for the vertical deflection of electron beam
c. Sinusoidal voltage for the vertical deflection of electron beam
d. Saw tooth voltage for the horizontal deflection of electron beam

ANSWER: Saw tooth voltage for the horizontal deflection of electron beam

32)   The rate at which fluid flows through a closed pipe can be determined by

a. Determining the mass flow rate
b. Determining the volume flow rate
c. Either (a) or (b)
d. None of these

ANSWER: Either (a) or (b)

33)   Conveyor – based method is used for the measurement of the flow of

a. Solids
b. Liquid
c. Gas
d. All of these

ANSWER: Solids

34)  For the measurement of flow rate of liquid, the method used is

a. Conveyor – based methods
b. Bourdon tube
c. Coriolis method
d. Thermal mass flow measurement

ANSWER: Coriolis method

35)   The devices used for flow obstruction is / are

a. Orifice plate
b. Venturi tube
c. Flow nozzle and dall flow tube
d. All of these

ANSWER: All of these

Electrical Measurement And Instrumentation MCQ

36)   To increase the current sensitivity below 10 mV, electronic instrument uses

a. Amplifiers
b. Modulator
c. Transducer
d. Oscillator

ANSWER: Amplifiers

37)   Electronic voltmeters can be designed to measure

a. Only very small voltages
b. Only very high voltages
c. Both very small and very high voltages
d. None of these

ANSWER: Both very small and very high voltages

38)   An RMS reading voltmeter can accurately measure voltages of

a. Sine waveforms
b. Square waveforms
c. Saw tooth waveforms
d. All of these
e. None of these

ANSWER: All of these

Electrical Measurement And Instrumentation MCQ