Q.1

Measurement of non-electrical quantity involves the following subsystems

  1. Amplifier block
  2. Display block
  3. Instrumentation block
  4. Transducer block
The correct sequence of these blocks is
  • 4, 1, 3, 2
  • 4, 3, 1, 2
  • 1, 3, 2, 4
  • 1, 2, 3, 4
Q.2

A linear displacement digital transducer generally uses

  • straight binary code
  • BCD
  • gray code
  • hexadecimal code
Q.3

Magnetic effect of current is used in

  • ammeters
  • voltmeters
  • wattmeters
  • ammeters, voltmeters, wattmeters and energy meters
Q.4

In a resistance strain gauge, G =stress =kg/cm2, R =Ω. The value of ΔR will be

  • 2 Ω
  • 3 Ω
  • 4 Ω
  • 1 Ω
Q.5

In figure the values of Rx and Cx are

Q.6

The term 'Poisson's ratio' is connected with

  • strain gauge
  • LVDT
  • Bourden tube
  • capacitance transducer
Q.7

A dynamometer wattmeter is connected in ac circuit. The measured power is

  • rms power
  • average power
  • peak power
  • instantaneous power
Q.8

Which of the following measurements using a dc potentiometer do not require standardisation of potentiometer?

  • Measurement of unknown voltage
  • Measurement of resistance
  • Measurement of unknown current
  • Calibration of voltmeter
Q.9

Which of the following are needed both for protection and metering?

  • Wattmeters
  • Instrument transformers
  • Energy meters
  • Power factor meters
Q.10

Magnetic flux density has the dimensions

  • MI-1T-2
  • M-1I-2T-2
  • ML-3T-2
  • MI-1T-3
Q.11

Loss of charge method is suitable for medium resistances.

  • True
  • False
Q.12

In two wattmeter method of 3 phase power measurement, when does one wattmeter read negative

  • when power factor is less than 0.5 lagging
  • when power factor is greater than 0.5 lagging
  • when power factor is less than 0.5
  • when power factor is unity
Q.13

Which of the following statement is correct for two wattmeters method of power measurement in 3 phase circuit?

  • Power can be measured by this method only for star connected loads
  • When two wattmeters have equal readings power factor is 0.5.
  • When power factor is 1, one of the wattmeters readings is zero
  • When the two wattmeter read equal and opposite, p.f. is zero.
Q.14

A digital frequency counter can be converted to DVM by addition of a suitable

  • voltage controlled oscillator
  • D/A converter
  • power amplifier
  • operational amplifier
Q.15

A meter with a resistance ofΩ and a full scale deflection of current of 1 mA is to be converted into voltmeter of 0 - 5 V range. The multiplier resistance should be

  • 490 Ω
  • 5000 Ω
  • 4900 Ω
  • 5100 Ω
Q.16

It is required to measure angular position. Out of the transducers

  1. Circular potentiometer
  2. LVDT
  3. E pick up
  4. Synchro
The proper devices are
  • 1, 2, 3, 4
  • 2 and 3
  • 1, 2, 4
  • 1 and 4
Q.17

In a thermocouple temperature transducer, the output voltage is usually measured by

  • high resistance ammeter
  • high resistance voltmeter
  • high resistance milli-voltmeter
  • none of the above
Q.18

A dynamometer wattmeter is connected in ac circuit. The reading will be

  • V-A product
  • average power
  • peak power
  • instantaneous power
Q.19

The household energy meter is

  • indicating instrument
  • recording instrument
  • integrating instrument
  • none of the above
Q.20

A moving iron instrument gives correct reading when used at

  • low frequencies
  • high frequencies
  • only one frequency
  • all frequencies upto a certain value
Q.21

The speed transducer using a drag cup rotor has the main advantage of

  • very high accuracy
  • low energy requirement
  • cheap construction
  • all of the above
Q.22

A voltmeter using thermocouples measures

  • rms value
  • peak value
  • average value
  • peak to peak value
Q.23

A standard cell of 1.V is used with a slide wire potentiometer. The balance was obtained atcm. When an unknown emf was connected, the balance was obtained atcm. The magnitude of unknown emf is

  • 1.39 V
  • 0.75 V
  • 13.9 V
  • 7.45 V
Q.24

Induction wattmeter can be used in

  • ac circuit only
  • dc circuit only
  • both ac and dc circuit
  • ac 3 phase only
Q.25

Assertion (A): Wien bridge can be used for measuring frequency.

Reason (R): A frequency meter forHz system has a frequency range oftoHz.

  • Both A and R are true and R is correct explanation of A
  • Both A and R are true but R is not correct explanation of A
  • A is true R is false
  • A is false R is true
Q.26

Consider the following operation in respect of Wheatstone bridge (Kb, denotes battery key, Kg denotes galvanometer key)

  1. open Kb
  2. close Kg
  3. close Kb
  4. open Kg
The correct sequence of operations is
  • 1, 2, 3, 4
  • 3, 1, 2, 4
  • 4, 3, 2, 1
  • 3, 2, 4, 1
Q.27

The power input and output in a device areW andW with each reading in doubt by ±W. The percentage uncertainty in losses is

  • ± 7.55%
  • ± 3.77%
  • ± 11.32%
  • ± 15.09%
Q.28

If eddy current damping is to be used, the disc of instrument should be

  • non-conducting and non-magnetic
  • conducting and magnetic
  • conducting and non-magnetic
  • non-conducting and magnetic
Q.29

Which of these has poor overload capacity?

  • PMMC instrument
  • Hot wire instrument
  • Dynamometer instrument
  • Both (a) and (c)
Q.30

Two voltmeters 0-V each having resistances of 5 kΩ andkΩ respectively and are connected in series. To ensure that neither of them goes beyond scale the total voltage which can be applied should be less than

  • 500 V
  • 400 V
  • 375 V
  • 250 V
Q.31

A meter coil has a resistance ofΩ and a full scale deflection current ofmA. To convert it into a voltmeter of 0-V range, the series resistance should be

  • 20 kΩ
  • 19.9 kΩ
  • 1.9 kΩ
  • 20.1 kΩ
Q.32

Which of these has a magnetic brake?

  • Thermocouple ammeter
  • Energy meter
  • Dynamometer wattmeter
  • Frequency meter
Q.33

The volt ratio box is basically a

  • potential divider
  • current transformer
  • a high resistance voltmeter
  • either (a) or (c)
Q.34

A sinusoidal ac voltage of amplitudeV is applied to a rectifying device which offersΩ resistance in forward direction and infinite resistance in backward direction. A moving coil ammeter is also connected in the circuit. The reading of ammeter will be

  • 10 A
  • 5 A
  • 3.185 A
  • 14.14 A
Q.35

In figure the bridge is balanced when Z4 is

  • 120∠70°
  • 187.5∠ - 10°
  • 187.5∠ - 70°
  • 333.3∠ - 70°
Q.36

The scale of moving iron instrument is linear.

  • True
  • False
Q.37

LVDT is a

  • pressure transducer
  • displacement transducer
  • velocity transducer
  • acceleration transducer
Q.38

In 3 phase power measurement by two wattmeter method, both wattmeters had equal reading. The power factor of load is

  • 1
  • 0.5 lagging
  • 0.5 leading
  • 0
Q.39

Amm long conductor has a resistance ofΩ. The change in resistance is 13.3 Ω and change in length is 1.6 mm under tension. The gauge factor is

  • 1.2
  • 1.6
  • 2.1
  • 2.6
Q.40

Two numbers are± 5 and±The sum of the numbers with range of doubt is

  • 760 ± 8
  • 760 ± 2
  • 760 + 8
  • 760 - 8
Q.41

Assertion (A): Schering bridge is a low voltage bridge.

Reason (R): Schering bridge is very commonly used for measurement of capacitance.

  • Both A and R are true and R is correct explanation of A
  • Both A and R are true but R is not correct explanation of A
  • A is true R is false
  • A is false R is true
Q.42

A variable reluctance tachometer hasteeth on rotor. The speed of shaft on which it is mounted inrpm. The frequency of output pulses is

  • 1800 per second
  • 3600 per second
  • 4800 per second
  • 5600 per second
Q.43

With a variable reluctance tachometer havingrotor teeth the count readscounts per minute. The speed in RPM is

  • 36
  • 60
  • 360
  • 3600
Q.44

When measuring phase angle between two waves using a CRO, the time base generator is connected to

  • X plate
  • Y plate
  • both X and Y plate
  • neither X nor Y plates
Q.45

A 0-V voltmeter has an accuracy of 0.of full scale reading. If voltage measured isV, the error is

  • 3%
  • 2%
  • 1.5%
  • .75%
Q.46

In Schering bridge, the potential of detector above earth potential is about

  • a few volts
  • 10 kV
  • 1000 V
  • either (a) or (b)
Q.47

Which instrument is based on induction principle?

  • Dynamometer wattmeter
  • Induction wattmeter
  • Energy meter
  • Both (b) and (c)
Q.48

Measuring of unknown voltage with a dc potentiometer loses its advantage of open circuit measurement when

  • primary circuit battery is changed
  • standardisation is done to compensate for drift
  • voltage is larger than range of potentiometer
  • range reduction by factor of 10 is employed
Q.49

It is required that a strain gauge has gauge factor ofThe proper strain gauge is

  • constantan strain gauge
  • nichrome strain gauge
  • semiconductor strain gauge
  • alloy strain gauge
Q.50

The dimensions of EMF are

  • ML2I-1T-3
  • M-1T-3
  • ML2I-2T-3
  • ML3I-1T-3
0 h : 0 m : 1 s