Q.1
Write the unit of magnetic flux?
  • wbm2\frac{wb}{m^2}m2wb​
  • wb
  • AT
  • AT/m
Q.2
Write the unit of magnetic field intensity?
  • wbm2\frac{wb}{m^2}m2wb​
  • wb
  • AT
  • AT/m
Q.3
Write the unit of magnetic flux density?
  • wbm2\frac{wb}{m^2}m2wb​
  • wb
  • AT
  • AT/m
Q.4
A moving-coil permanent-magnet instrument can be used as flux meter
  • by using a low resistance shunt
  • by using a high series resistance
  • by eliminating the control springs
  • by making control springs of large moment of inertia
Q.5
To measure radio frequency, the suitable frequency meter is
  • Weston frequency meter
  • reed vibrator frequency meter
  • heterodoxy frequency meter
  • electrical resonance frequency meter
Q.6
In a Schering bridge the potential of the detector above earth potential is
  • a few volts only
  • 1 kV
  • 5 kV
  • 10 kV
Q.7
________ cooling is the process of dissipating the armature and field winding losses to a cooling medium circulating within the winding insulation wall
  • Direct
  • Indirect
  • Conventional
  • Any of the above
Q.8
The disc of an instrument using eddy current damping should be of
  • conducting and magnetic material
  • non-conducting and magnetic material
  • conducting and non-magnetic material
  • none of the above
Q.9
E.m.f. of a Weston cell is accurately measured by
  • electrostatic voltmeter
  • hot wire voltmeter
  • isothermal voltmeter
  • electrodynamic voltmeter
Q.10
In a 3-phase power measurement by two wattmeter method, both the watt meters had identical readings. The power factor of the load was
  • unity
  • 0.8 lagging
  • 0.8 leading
  • zero
Q.11
The switch board instruments
  • should be mounted in vertical position
  • should be mounted in horizontal position
  • either (A) or (B)
  • neither (A) nor (B)
Q.12
In a Weston synchronoscope, the fixed coils are connected across
  • bus-bars
  • incoming alternator
  • a lamp
  • none of the above
Q.13
An ohmmeter is a
  • moving iron instrument
  • moving coil instrument
  • dynamometer instrument
  • none of the above
Q.14
An ammeter is a
  • secondary instrument
  • absolute instrument
  • recording instrument
  • integrating instrument
Q.15
Most common form of A.C. meters met with in every day domestic and industrial installations are
  • mercury motor meters
  • commutator motor meters
  • induction type single phase energy meters
  • all of the above
Q.16
Which of the following is measured by using a vector voltmeter ?
  • Amplifier gain and phase shift
  • Filler transfer functions
  • Complex insersion loss
  • All of the above
Q.17
A voltage of aboutV can be measured
  • directly by a potentiometer
  • a potentiometer in conjunction with a volt ratio box
  • a potentiometer in conjunction with a known resistance
  • none of the above
Q.18
It is required to measure the true open circuit e.m.f. of a battery. The best device is
  • voltmeter
  • Ammeter and a known resistance
  • 'potentiometer
  • None of the above
Q.19
To avoid the effect of stray magnetic field in A.C. bridges we can use
  • magnetic screening
  • Wagner earthing device
  • wave filters
  • any of the above
Q.20
The resistance in the circuit of the moving coil of a dynamometer wattmeter should be
  • almost zero
  • low
  • high
  • none of the above
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