Olete.in – MCQs, Mock Tests & Government Job Prep | Lab Measurement (TDR, VNA, Picoprobes) Measurement and Instrumentation MCQ Set 2

A moving-coil permanent-magnet instrument can be used as ________ by using a low resistance shunt.

1. Ammeter
2. Voltmeter
3. Flux-meter
4. Ballistic galvanometer

✅ Correct Answer: 1

______ is an instrument which measures the insulation resistance of an electric circuit relative to earth and one another,

1. Tangent galvanometer
2. Meggar
3. Current transformer
4. None of the above

✅ Correct Answer: 2

An induction wattmeter can be used for

1. Both D.C. and A.C.
2. D.C. only
3. A.C. only
4. Any of the above

✅ Correct Answer: 2

Murray loop test can be used for location of

1. Ground fault on a cable
2. Short circuit fault on a cable
3. Both the ground fault and the short-circuit fault
4. None of the above

✅ Correct Answer: 3

In an A.C. coordinate potentiometer, the currents in the phase and quadrature potentiometer are adjusted to be

1. Out of phase by 90°
2. Out of phase by 60°
3. Out of phase by 30°
4. Out of phase by 0°

✅ Correct Answer: 1

For measuring a very high resistance we should use

1. Kelvin's double bridge
2. Wheat stone bridge
3. Meggar
4. None of the above

✅ Correct Answer: 3

The function of shunt in an ammeter is to

1. By pass the current
2. Increase the sensitivity of the ammeter
3. Increase the resistance of ammeter
4. None of the above

✅ Correct Answer: 1

Which of the following is an essential part of a motor meter?

1. An operating torque system
2. A braking device
3. Revolution registering device
4. All of the above

✅ Correct Answer: 4

_______ instruments are those which measure the total quantity of electricity delivered in a particular time.

1. Absolute
2. Indicating
3. Recording
4. Integrating

✅ Correct Answer: 4

In a low power factor wattmeter the pressure coil is connected

1. To the supply side of the current coil
2. To the load side of the current coil
3. In any of the two meters at connection
4. In any of the two meters at connection

✅ Correct Answer: 2

A direct current can be measured by

1. A D.C. potentiometer directly
2. A D.C. potentiometer in conjunction with a standard resistance
3. A D.C. potentiometer in conjunction with a volt ratio box
4. None of the above

✅ Correct Answer: 2

If the current in a capacitor leads the voltage by 80°, the loss angle of the capacitor is

1. 10°
2. 80°
3. 120°
4. 170°

✅ Correct Answer: 1

Commonly used standard capacitor is

1. Spherical type
2. Concentric cylindrical type
3. Electrostatic type
4. Multilayer parallel plate type

✅ Correct Answer: 2

Most sensitive galvanometer is

1. Elastic galvanometer
2. Vibration galvanometer
3. Duddlb galvanometer
4. Spot ballistic galvanometer

✅ Correct Answer: 4

Which of the following is measured by using a vector voltmeter?

1. Amplifier gain and phase shift
2. Filler transfer functions
3. Complex insertion loss
4. All of the above

✅ Correct Answer: 4

Damping of the Ballistic galvanometer is made small to

1. Get first deflection large
2. Make the system oscillatory
3. Make the system critically damped
4. Get minimum overshoot

✅ Correct Answer: 1

In a vibrating reed frequency meter the natural frequencies of two adjacent reeds have a difference of

1. 0.1 Hz
2. 0.25 Hz
3. 0.5 Hz
4. 1.5 Hz

✅ Correct Answer: 3

Basically a potentiometer is a device for

1. Comparing two voltages
2. Measuring a current
3. Comparing two currents
4. Measuring a voltage

✅ Correct Answer: 1

For measuring current at high frequency we should use

1. Moving iron instrument
2. Electrostatic instrument
3. Thermocouple instrument
4. None of the above

✅ Correct Answer: 3

A ________ device prevents the oscillation of the moving system and enables the latter to reach its final position quickly

1. Deflecting
2. Controlling
3. Damping
4. None of the above

✅ Correct Answer: 3

A potentiometer may be used for

1. Measurement of resistance
2. Measurement of current
3. Calibration of ammeter
4. All of the above

✅ Correct Answer: 4

The electrical power to a Meggar is provided by

1. Battery
2. Permanent magnet D.C. generator
3. AC. generator
4. None of the above

✅ Correct Answer: 2

To avoid the effect of stray magnetic field in A.C. bridges we can use

1. Magnetic screening
2. Wagner earthing device
3. Wave filters
4. Any of the above

✅ Correct Answer: 1

Volt box is a component to

1. Extend voltage range
2. Measure voltage
3. Compare voltage in a box
4. None of the above

✅ Correct Answer: 1

Two holes in the disc of energy meter are drilled at the opposite sides of the spindle to

1. Improve its ventilation
2. Eliminate creeping at no load
3. Increase its deflecting torque
4. Increase its braking torque

✅ Correct Answer: 2

Which of the following instruments indicate the instantaneous value of the electrical quantity being measured at the time at which it is being measured?

1. Absolute instruments
2. Indicating instruments
3. Recording instruments
4. Integrating instruments

✅ Correct Answer: 2

The pointer of an indicating instrument should be

1. Very light
2. Very heavy
3. Either (A) or (B)
4. Neither (A) nor (B)

✅ Correct Answer: 1

A phase shifting transformer is used in conjunction with

1. D.C. potentiometer
2. Drysdale potentiometer
3. A.C. coordinate potentiometer
4. Crompton potentiometer

✅ Correct Answer: 2

The desirable static characteristics of a measuring system are

1. Accuracy and reproducibility
2. Accuracy, sensitivity and reproducibility
3. Drift and dead zone
4. Static error

✅ Correct Answer: 2

In an Anderson bridge, the unknown inductance is measured in terms of

1. Known inductance and resistance
2. Known capacitance and resistance
3. Known resistance
4. Known inductance

✅ Correct Answer: 2

The resistance in the circuit of the moving coil of a dynamometer wattmeter should be

1. Almost zero
2. Low
3. High
4. None of the above

✅ Correct Answer: 3

Which of the following devices may be used for extending the range of instruments?

1. Shunts
2. Multipliers
3. Current transformers
4. All of the above

✅ Correct Answer: 4

Which of the following essential features is possessed by an indicating instrument? (A)

1. Deflecting device
2. Controlling device
3. Damping device
4. All of the above

✅ Correct Answer: 4

In a Meggar controlling torque is provided by (A)

1. Spring
2. Gravity
3. Coil
4. Eddy current

✅ Correct Answer: 3

The ratio of maximum displacement deviation to full scale deviation of the instrument is called

1. Static sensitivity
2. Dynamic deviation
3. Linearity
4. Precision or accuracy

✅ Correct Answer: 3

Various adjustments in an energy meter include

1. Light load or friction
2. Lag and creep
3. Overload and voltage compensation
4. All of the above

✅ Correct Answer: 4

E.m.f. of a Weston cell is accurately measured by

1. Electrostatic voltmeter
2. Hot wire voltmeter
3. Isothermal voltmeter
4. Electrodynamic voltmeter

✅ Correct Answer: 1

An ammeter is a

1. Secondary instrument
2. Absolute instrument
3. Recording instrument
4. Integrating instrument

✅ Correct Answer: 1

The stator of phase shifting transformer for use in conjunction with an A.C. potentiometer usually has a

1. Single-phase winding
2. Two-phase winding
3. Three-phase winding
4. Any of the above

✅ Correct Answer: 2

According to application, instruments are classified as

1. Switch board
2. Portable
3. Both (A) and (B)
4. None of the above

✅ Correct Answer: 3

The switch board instruments

1. Should be mounted in vertical position
2. Should be mounted in horizontal position
3. Either (A) or (B)
4. Neither (A) nor (B)

✅ Correct Answer: 1

In a Schering bridge the potential of the detector above earth potential is

1. A few volts only
2. 1 kV
3. 5 kV
4. 10 kV

✅ Correct Answer: 1

A multi-range instrument has

1. Multiple shunt or series resistances inside the meter
2. Multi-coil arrangement
3. Variable turns of coil
4. Multi range meters inside the measurement system

✅ Correct Answer: 1

In a low power factor wattmeter the compensating coil is connected

1. In series with current coil
2. In parallel with current coil
3. In series with pressure coil
4. In parallel with pressure coil

✅ Correct Answer: 3

A moving-coil permanent-magnet instrument can be used as flux-meter

1. By using a low resistance shunt
2. By using a high series resistance
3. By eliminating the control springs
4. By making control springs of large moment of inertia

✅ Correct Answer: 3

Which of the following are integrating instruments?

1. Ammeters
2. Voltmeters
3. Watt-meters
4. Ampere-hour and watt-hour meters

✅ Correct Answer: 4

A Weston synchronoscope is a

1. Moving coil instrument
2. Moving iron instrument
3. Dynamometer instrument
4. None of the above

✅ Correct Answer: 3

Wattmeter cannot be designed on the principle of

1. Electrostatic instrument
2. Thermocouple instrument
3. Moving iron instrument
4. Electrodynamic instrument

✅ Correct Answer: 3

Which of the following meters are not used on D.C. circuits?

1. Mercury motor meters
2. Commutator motor meters
3. Induction meters
4. None of the above

✅ Correct Answer: 3

. If an inductance is connected in one arm of bridge and resistances in the remaining three arms

1. The bridge can always be balanced
2. he bridge cannot be balanced
3. The bridge can be balanced if the resistances have some specific values
4. None of the above

✅ Correct Answer: 2

Which of the following properties a damping oil must possess?

1. Must be a good insulator
2. Should be non-evaporating
3. Should not have corrosive action upon the metal of the vane
4. All of the above

✅ Correct Answer: 4

In a portable instrument, the controlling torque is provided by

1. Spring
2. Gravity
3. Eddy currents
4. All of the above

✅ Correct Answer: 1

The adjustment of position of shading bands, in an energy meter is done to provide

1. Friction compensation
2. Creep compensation
3. Braking torque
4. None of the above

✅ Correct Answer: 1

For measurement of inductance having high value, we should use

1. Maxwell's bridge
2. Maxwell Wien bridge
3. Hay's bridge
4. Any of the above

✅ Correct Answer: 3