Q.1
Which of these is NOT true for systematic errors?
  • They arise due to errors in the measuring instruments used.
  • Repeating the observations or increasing the sample size can eliminate them
  • They are reproducible inaccuracies that are consistently in the same direction.
  • They arise from misinterpretation of procedure
Q.2
It is required to measure angular position. Out of the transducers Circular potentiometerLVDTE pick upSynchro The proper devices are
  • 1, 2, 3, 4
  • 2 and 3
  • 1, 2, 4
  • 1 and 4
Q.3
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.4
Loss of charge method is suitable for medium resistances.
  • True
  • False
Q.5
A dynamometer wattmeter is connected in ac circuit. The measured power is
  • rms power
  • average power
  • peak power
  • instantaneous power
Q.6
Induction wattmeter can be used in
  • ac circuit only
  • dc circuit only
  • both ac and dc circuit
  • ac 3 phase only
Q.7
A moving iron instrument gives correct reading when used at
  • low frequencies
  • high frequencies
  • only one frequency
  • all frequencies upto a certain value
Q.8
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.9
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.10
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.11
A voltmeter using thermocouples measures
  • rms value
  • peak value
  • average value
  • peak to peak value
Q.12
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.13
A dynamometer wattmeter is connected in ac circuit. The reading will be
  • V-A product
  • average power
  • peak power
  • instantaneous power
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
Which of the following are needed both for protection and metering?
  • Wattmeters
  • Instrument transformers
  • Energy meters
  • Power factor meters
Q.16
Which of the following is true about an impulse voltage?
  • It is a unidirectional voltage
  • Chopped impulse flashover does not occur
  • Time taken to rise is equal to time taken to fall
  • RMS value is always less than 50% of average value
Q.17
Assertion (A): A hot wire ammeter has a cramped scale.Reason (R): The heat is proportional to square of current.
  • 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.18
Potentiometer method of dc voltage measurement is more accurate than direct measurement using a voltmeter because
  • it loads the circuit to maximum extent
  • it loads the circuit moderately
  • it does not load the circuit at all
  • it uses centre zero galvanometer instead of Voltmeters
Q.19
A moving coil instrument has a resistance of 0.5 Ω and a full scale deflection of 0.1 A. To convert it into an ammeter of 0-A the shunt resistance should be
  • 0.004 Ω
  • 0.005 Ω
  • 0.05 Ω
  • 0.1 Ω
Q.20
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.21
In a resistance strain gauge, G =stress =kg/cmR =Ω. The value of ΔR will be
  • 2 Ω
  • 3 Ω
  • 4 Ω
  • 1 Ω
Q.22
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.23
Magnetic flux density has the dimensions
  • MI-1T-2
  • M-1I-2T-2
  • ML-3T-2
  • MI-1T-3
Q.24
The angle δ for a mica capacitor is about
  • 25°
  • 15°
  • 5°
  • 1°
Q.25
The Lissajous pattern observed on screen of CRO is a straight line inclined atto x axis. If X-plate input is 2 sin ωt, the Y-plate input is
  • 2 sin ωt
  • 2 sin (ωt + 45°)
  • 2 sin (ωt - 45°)
  • 22 sin ωt + 45°)
Q.26
A digital voltmeter has a read out range from 0 tocounts. If the full scale reading is 9.V, the resolution is
  • 1 V
  • 0.01 V
  • 1 mV
  • 1 μV
Q.27
Consider the following statements: In a differential amplifier using JFET, the differential output offset is due to mismatch between FET parametersdifference in values of resistances used in circuitvariation in supply voltage. Of the statements, the correct statements are
  • 1 and 2
  • 1, 2, 3
  • 2, 3
  • 1, 3
Q.28
The coil of a moving coil meter hasturns, ismm long andmm wide. The control torque isx 10-6 N-m on full scale. If B = 1 Wb/mrange of meter is
  • 1 mA
  • 2 mA
  • 3 mA
  • 4 mA
Q.29
In a strain measuring device using a strain gauge, the output quantity is
  • voltage
  • resistance
  • impedance
  • either (a) or (b)
Q.30
Two resistors R1 =Ω ±and R2 =Ω ±are connected in series. The total resistance is
  • 111 ± 0 Ω
  • 111 ± 2.778 Ω
  • 111 ± 5.55 Ω
  • 111 ± 7.23 Ω
0 h : 0 m : 1 s