MCQ
21. An instrument transformer is used to extend the range of-
Induction instrument
Electrostatic instrument
Moving coil instrument
Any of the above
22. In a moving coil instrument, the deflecting torque is proportional to-
Current
Square of the current
Squareroot of the current
Sine of the measurand
23. For measurement of inductance having high value, we should use-
Maxwell's bridge
Maxwell Wien bridge
Hay's bridge
Any of the above
24. The pointer of an indicating instrument should be--
Very light
Very heavy
Either (a) or (b)
Neither (a) nor (b)
25. A moving iron instrument can be used for-
DC only
AC only
Both DC and AC
None of the above
26. The internal resistance of an ammeter should be-
Very small
High
Medium
Infinity
27. Alternating current is measured by-
Induction ammeter
Permanent magnet type ammeter
Electrostatic ammeter
Moving iron repulsion type voltmeter
28. An ohmmeter is a---
Moving iron instrument
Moving coil instrument
Dynamometer instrument
None of the above
29. Ryall crest voltmeter is used for measurement of--
AC voltage of any form
Low-frequency voltage
High-DC voltage
High-AC voltage
30. In a Weston synchronoscope, the fixed coils are connected across-
Bus-bars
A lamp
Incoming alternator
None of the above
31. In a dynamometer 3-phase power factor meter, the planes of the two moving coils are at----
0°
60°
90°
120°
32. An oscilloscope indicates-
Peak to peak value of voltage
DC value of voltage
RMS value
Average value
33. Direct method is used to measure-
Length
Pressure
Temperature
Voltage
34. The operating voltage of a Meggar is about-
6V
12V
40V
100V
35. In an energy meter braking torque is produced to--
Safeguard it against creep
Brake the instrument
Bring energy meter to stand still
Maintain steady speed and equal to driving torque
36. The disc of an instrument using eddy current damping should be of-
Conducting and magnetic material
Non-conducting and magnetic material
Conducting and nonmagnetic material
None of the above
37. In order to achieve high accuracy, the slide wire of a potentiometer should be-
As long as possible
As short as possible
Neither too small nor too large
Very thick
38. Commonly used instruments in power system measurement are-
Induction
Rectifier
Moving coil or iron
Electrostatic
39. Ampere is one of the-
Supplementary units
Derived units
Base units
Units used to measure charge
40. A dynamometer wattmeter can be used for-
DC only
AC only
Both DC and AC
Any of the above