An induction wattmeter can be used for ac only.
Loading effect is primarily caused by instruments having
Capacitive transducer is superior to inductive type for measurement of capacitance because of
In Weston synchronoscope the fixed coils are connected across
Which of the following is not a transducer in true sense?
Which of the following can be used for measuring capacitance?
Consider the following statements about mutual inductances:
The total insulation resistance consists of insulation volume resistance and surface leakage resistance.
Assertion (A): Energy meters use induction principle.
Reason (R): Induction wattmeter is less accurate than a dynamometer wattmeter.
The phenomenon of creep occurs in
Magnetic deflection sensitivity is defined as
Which of the following is active transducer?
The dimensions of permittivity are
The sensitivity of a potentiometer can be increased by
The coding system generally used in digital telemetry is
Assertion (A): A dc potentiometer measures the true open circuit emf of a source.
Reason (R): At balance point, a dc potentiometer does not draw any current from the source.
Wagner earthing device is used to eliminate error due to
RTD is generally suitable for temperature up to
The adjustment of position of shading bands, in an energy meter, is done to provide
Shaft encoder is used to measure
Assertion (A): Hay's bridge in particularly suitable for measuring inductance having a comparatively low resistance.
Reason (R): In Hay's bridge the value of frequency supply must be known.
To measure a resistance of about 8 ohms we should use
Which of the following effects is used in measurement of magnetic flux?
The range of RTD using platinum is about
To avoid the effect of stray magnetic fields in ac bridge we can use
The resistance of voltmeter affects the accuracy of measurement in loss of charge method.
Assertion (A): In a CRT, grid is kept at negative potential with respect to cathode.
Reason (R): The function of grid in an electronic tube is to control the number of electrons.
A dynamometer wattmeter can be used for
A D' Arsonval galvanometer is a
Assertion (A): When frequencies of signals fed to X and Y plates of CRO are multiples of each other, Lissajous pattern is displayed on screen.
Reason (R): In a CRO, the vertical deflection is proportional to voltage applied to Y plates.
The device having highest photo sensitivity is
Which of the following closely represents the resistance-temperature characteristics of thermistor?
Consider the following statements regarding electro-dynamometer type indicating instrument
It can be used for measuring
Which of these instruments has highest power consumption?
For measuring temperatures below 800°C with high accuracy, the best instrument is
Panel instruments are generally mounted vertically.
A digital voltmeter has a 4 1/2 digit display. The 1 V range can measure voltage up to
Consider the following statements as regards induction and dynamometer wattmeters
A resistance strain gauge is usually
In a hot wire instrument, the deflection is proportional to
Schering bridge is used to measure
A power factor meter has
In portable instruments, damping is provided by
If A =± 8 and B =±A - B with range of doubt is
Assertion (A): Many instruments use eddy current damping.
Reason (R): Eddy currents set up a magnetic flux which opposes the original movement which generates them.
A Maxwell's bridge has the unknown inductance in one arm and resistance in the other three arms.
Assertion (A): Secondary instruments require calibration at frequent intervals.
Reason (R): Secondary instruments have many errors.
A permanent magnet moving coil meter can be used as
Assertion (A): In a CRT, grid is kept at negative potential with respect to cathode.
Reason (R): The function of grid in an electronic tube is to control the number of electrons.
In a semiconductor strain gauge, the ohmic electrical contacts are generally made of