Q.1
In a ballistic galvanometer, a charge ofμC gives a first swing of 25°. The charge required to cause first swing ofis
  • 200 μC
  • 400 μC
  • 50 μC
  • 25 μC
Q.2
As per BIS there are 6 accuracy classes of instruments.
  • True
  • False
Q.3
Assertion (A): When a wattmeter is used for low impedance loads, the pressure coil is connected across the load.Reason (R): A wattmeter measures apparent power.
  • 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.4
An LVDT is used to measure displacement. The LVDT feeds a Voltmeter of 0-5 V range through again amplifier. For a displacement 0.5 mm the output of LVDT is 2 mV. The sensitivity of instrument is
  • 0.1 V/mm
  • 0.5 V/mm
  • 1 V/mm
  • 5 V/mm
Q.5
A piezoelectric force transducer has a charge sensitivity ofpC/N. It is connected to a charge amplifier and overall gain of transducer and amplifier ismV/N. The gain of amplifier is
  • 1 mV/pC
  • 1.5 mV/pC
  • 2.5 mV/pC
  • 4 mV/pC
Q.6
A moving coil instrument has a resistance of 0.6 Ω and full scale deflection at 0.1 A. To convert it into an ammeter of 0-A range, the resistance of shunt should be
  • 0.6 Ω
  • 0.06 Ω
  • 0.1 Ω
  • 0.004 Ω
Q.7
Which of the following voltmeters would you use for measuring voltage acrosskΩ resistance?
  • Voltmeter having a resistance of 5 kΩ
  • Voltmeter having a sensitivity of 1 kW/V
  • Voltmeter having sensitivity of 10 kW/V
  • None of the above
Q.8
If reference sound pressure P0 is 2 x 10-5 N/ma sound pressure ofdB is equal to
  • 0.632 N/m2
  • 0.707 N/m2
  • 0.835 N/m2
  • 0.925 N/m2
Q.9
Assertion (A): De sauty's bridge is suitable only for pure capacitor.Reason (R): Capacitors are mostly perfect.
  • 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.10
In which of the transformer is the secondary nearly short circuited under normal operating conditions?
  • CT
  • PT
  • Distribution transformer
  • Power transformer
Q.11
A single phase energy meter has the ratingresolutions/ kWh. If aW electric gadget is used for 4 hours, the energy meter will make
  • 1200 revolutions
  • 1800 revolutions
  • 2100 revolutions
  • 2400 revolutions
Q.12
In a CRO which of the following is not a part of electron gun
  • cathode
  • grid
  • accelerating anode
  • X - Y plates
Q.13
To increase Q factor of a coil, the wire should be
  • long
  • thin
  • thick
  • long and thin
Q.14
An ammeter of 0-A range has a guaranteed accuracy ofof full scale reading. The current measured is 5 A. The limiting error is
  • 2%
  • 2.5%
  • 4%
  • 5%
Q.15
In 3 phase power measurement by two wattmeter method, the reading of one wattmeter is zero. The power factor of load is
  • 1
  • 0.5
  • 0
  • 0.8
Q.16
The coil of a moving iron instrument has a resistance ofΩ and an inductance of 1 H. It readsV when aV dc is applied. If series resistance isΩ, its reading when fed byV,Hz ac will be
  • 260 V
  • 252 V
  • 250 V
  • 248 V
Q.17
Which of the following instruments can be used to measure AC current only?
  • Permanent Magnet Type ammeter
  • Induction type ammeter
  • Moving iron voltmeter
  • Moving iron ammeter
Q.18
The thermocouple instrument will measure
  • Current
  • Voltage
  • Flux
  • None of the above
Q.19
The thermocouple instruments do not have
  • High sensitivity
  • Absence of frequency error
  • Independence of ambient temperature
  • High degree of measuring accuracy
Q.20
Wien bridge is useful for measuring
  • Very high frequency
  • Low frequency
  • Medium frequency
  • High frequency
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