# 50 TOP MEASUREMENT and INSTRUMENTS Objective Questions and Answers pdf

1. Hysteresis of an instrument means:
a) The change in the same reading when input is first increased and then decreased
b) The reliability of the instrument
c) The repeatability of the insrument
d) The inaccuracy due to change in temperature

2. In which part of the scale does the pointer indicate more accurately
a) In the first third of the cycle
b) In the first half of the cycle
c) In about middle of the scale
d) In the last third of the cycle

3. For measuring an unknown electrical quantity, select the meter with
a) Highest range and work down
b) Lowest range and work up
c) Middle range and can be work up or down depending
d) Any of the above

4. The ratio of maximum displacement deviation to the full scale deviation of the instrument is called:
a) Static sensitivity
b) Accuracy
c) Linearity
d) Precision

5. A 150 V moving iron voltmeter of accuracy class 1.0 reads 75 V when used in a circuit under a standard conditions. The maximum possible percentage error in the reading is:
a) 0.5
b) 1.0
c) 2.0
d) 4.0

6. The relative error is the:
a) Difference of the measured value and the true value
b) Ratio of absolute error to the measured value of the quantity under measurement
c) Ratio of the absolute error to the true value of the quantity under measurement
d) Ratio of the probable error to the true value of the quantity under measurment

7. The moving iron voltmeters are likely:
a) To indicate the same value of the ac as on dc
b) To indicate higher value of ac than on dc
c) To indicate lower value of ac than on dc
d) The moving iron instruments should not be used for dc measurment

8. The power measurement in a balanced 3-phase circuit can be done by:
a) One wattmeter method
b) Two wattmeter method
c) Three wattmeter method
d) Any of the above method

9. Anderson’s bridge is a modification of:
a) Maxwell’s wien bridge
b) Hay’s bridge
c) Schering bridge
d) Owen bridge

10. Ballastic tests are used in magnetic measurements for the determination of:
a) Flux density of the specimen
b) B-H curve of the specimen
c) Hysteresis loop of the specimen
d) All the above

11. Anderson Bridge is used to measure:
a) L
b) C
c) V
d) I

12. Hay’s Bridge is suitable for the measurement of:
a) Inductances with Q>10
b) Inductances with Q<10
c) Capacitors with high dissipation factor
d) Capacitors with low dissipation factor

13. The frequency can be measured by using:
a) Wien’s bridge
b) De Sauty’s bridge
c) Schering’s bridge
d) Anderson’s bidge

14. The ballistic galvanometer is usually lightly damped so that:
a) It may oscillate
b) It may remain stable
c) Amplitude of the first swing is large
d) Amplitude of the first swing is small

15. B-H Curve is used to determination of:
a) Hysteresis loss
b) Iron loss
c) Eddy current loss
d) Both (a) and (b)

16. Magnetic materials can be tested by:
a) Self inductance bridge
b) Cambell’s mutual inductance bridge
c) AC potentiometer
d) All the above

17. A PMMC instrument can be used as a fluxmeter by:
a) Using low resistance shunt
b) Removing the control spring
c) Making the control springs of large moment of inertia
d) Using a high series resistance

18. Open circuit fault in a cable can be located by:
a) Blavier’s test
b) Capacity test
c) Varley loop test
d) Murray loop test

19. In CRO the time base signal is applied to:
a) Y-plates
b) X-plates
c) Either X-plate or Y-plate
d) Both X-plate and Y-plate

20.In CRO astigmatism is:
a) Source of generating fast electrons
b) Media for absorbing secondary emission electrons
d) Time-delay control in the vertical deflection system

21. The main advantage of crystal oscillator is that its output is:
a) A Constant frequency range
b) DC
c) 50 Hz to 60 Hz
d) Variable frequency

22. Which of the following statement is true of phase-shift type and Wien-bridge type R-C oscillators:
a) Both use positive feedback
b) The former uses positive feedback only whereas the latter uses both positive and negative feedback
c) The former uses both positive and negative feedback
d) Both use negative feedback

23. Moving iron and PMMC instruments can be distinguished from each other by looking at:
a) Pointer
b) Terminal size
c) Scale
d) Scale range

24. In a dynamo-meter type of moving coil instrument a swamping resistance is provided inorder to:
a) Control the deflection torque
b) Reduce the bulk of the moving system
c) Reduce the current flowing through the moving coil
d) Provide equal time constant for moving coil and fixed coil, when used for ac measurement

25. The deflection of hot-wire instrument depends on:
a) Instantaneous value of alternating current
b) Average value of current
c) RMS value of the alternating current
d) Voltage

26. If two meters X and Y requires 40mA and 50mA respectively, to give full scale deflection, then:
a) X is more sensitive
b) Y is more sensitive
c) Both X and Y are equally sensitive
d) It would not be possible to access the sensitivity on the basis of the given data

27. The reliability of the instrument refer to:
a) Measurement of changes due to temperature variations
b) Degree to which repeatability continues to remain within specified limits
c) The life of the instrument
d) The extent to which the characteristics remain linear

28. The damping torque must operate only when the moving system of the indicating instrument is:
a) Actually moving
b) Stationary
c) Just starting to move
d) Near its full deflection

29. If a voltmeter is connected, like an ammeter in series to the load:
a) The measurement reading will be too high
b) Almost no current will flow in the circuit
c) The meter will burn
d) An instantaneously high current will flow

30. Preferred material for permanent magnet is:
a) Stainless steel
b) Alnico
c) Tungsten steel
d) Soft iron

31. Air friction damping is used in the instruments which is:
a) Moving iron
b) Moving coil
c) Induction
d) Hot wire

32. PMMC instrument gives uniform scale because:
a) It uses spring control
b) It uses eddy current damping
c) The deflection torque is proportional to the instrument current
d) Both (a) and (c)

33.An instrument that is capable of measuring only dc is:
a) Moving coil
b) Moving iron
c) Thermo couple
d) None of the above

34. Maxwell-Wien bridge is used to measure:
a) Inductance
b) Capacitance
c) Dielectric loss
d) Frequency

35.A ballistic galvanometer is used to measure:
a) Charge
b) Current
c) Voltage
d) Frequency

36. ____ factor is the ratio of total flux to the useful flux in a magnetic circuit:
a) Form factor
b) Leakage
c) Utility
d) Dispersion

37. For eliminating the effect of earth capacitance from the bridge network we use:
a) Wagner’s earthing device
b) High voltage at low frequency
c) Low voltage at high frequency
d) Campbell-maxwell device

38. The most commonly used null deflector in a power frequency ac bridge is a:
a) Vibration galvanometer
b) D’Arsanval galvanometer
c) Ballistic galvanometer
d) Tachometer

39. For measuring emf of a standard cell we use:
a) Galvanometer
b) Potentiometer
c) Zener reference
d) Electro-dynamic voltmeter

40.Loss of charge method is used to measure:
a) Low R
b) High R
c) Low L
d) High L

41. Megger is an instrument used for the measurement of:
a) High resistance and insulation resistance
b) Medium resistance
c) Low resistance
d) Leakage current

42. Vibration reeds are employed in:
a) Frequency meter
b) Power factor meter
c) Synchroscope
d) Megger

43. Kelvin double bridge is best suited for the measurement of:
a) Inductance
b) Capacitance
c) Low resistance
d) High resistance

44. Introduction of dielectric:
a) Increases the capacitance
b) Reduces the breakdown voltage
c) Reduces the mechanical voltage
d) Increases the size of the capacitor

45. The material used to make standard resistance is:
a) Manganin
b) Aluminium
c) Nichrome
d) Platinum

46. Which of the following instruments have least torque/weight ratio:
a) Dynamometer type
b) PMMC
c) Attraction type moving iron
d) Repulsion type moving iron

47. The instrument having its deflection depends upon average value is:
a) Moving iron
b) Hot wire
c) Rectifier type
d) Induction type

48. Which of the following instruments can be used for full scale deflection of 300o:
a) PMMC
b) Induction type
c) Hot wire
d) Electrostatic

49.While testing cables the galvanometer used should be initially short-circuited in order to protect it from sudden initial inrush currents as the cable have:
a) A low value of initial resistance
b) A low value of initial capacitance
c) A high value of initial capacitance
d) Both (a) and (b)

50. A Ohmmeter is basically:
a) A ammeter
b) A voltmeter
c) A multimeter
d) None of the above

## 13 thoughts on “50 TOP MEASUREMENT and INSTRUMENTS Objective Questions and Answers pdf”

1. suneel kumar says:

thanks sir

2. limenih says:

good!!!A great thanks……

3. JAGANNATH DAS says:

sir,
I request to MCQ Questions and Answers 50 top Measurement and Instrument objective questions send me my email. Thank You.

4. rajesh says:

18 bit ans d

1. sai says:

correct answer is capacity test only. Option B.

5. rajesh says:

13 bit Ans A

1. sai says:

Yes, It is used to measure audio frequencies.

6. mohit says:

question 9 ansd

7. kiddo says: