MM All Units MCQ

8/11/2019 MM All Units MCQ

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Unit 1.I ntr oduction to Measurement System

and Unit 2.Static Characteri stics

1. Complete solution of any mechanical engineering design problem requires

a. Empirical method

b. Rational method

c. Experimental Method*d. All of the above

2. Indirect method of measurement incorporatesa. Zero translation

b. One Translation

c. Two translation*d. b and c both

3. Which measurement instrument is an example of Primary measurement?

a. Thermometerb. Pressure Gauge

*c. Meter Rod

d. Voltmeter

4. Which measurement instrument is an example of Tertiary measurement?

a. Vernier Caliper

*b. Bourdons Tube Pressure Gaugec. Thermometer

d. Steel rule

5. Which measurement instruments are so constructed that the quantity being measured can only be measured

by observing the output indicated by the instrument?

a. Absolute Instruments

*b. Secondary Instruments

c. A and b bothd. None of the above

6. Signal that vary in a continuous fashion and take on an infinite number of values in any given range are

called?

a. Digital Signals

*b. Analog Signalsc. Independent Signals

d. Dependent Signals

7. The last digit of any digital number in Digital Instruments is rounbed to which value of the last digit?

a. +-1.0b. +-5.0

*c. +-0.5d. +-1.5

8. A measurement instrument is expected to performa. Indicating function

b. Recording function

c. Controlling function*d. All of the above


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9. A generalized measurement system has which basic element?a. Variable Conversion element

b. Data presentation element

c. Primary sensing element

*d. All of the above

10. The measurement of a quantity is

a. An act of comparison of an unknown quantity whose accuracy may be known or may not be known*b. An act of comparison of an unknown quantity with another quantity

c. An act of comparison of an unknown quantity with a predefined acceptable standard which is accurately

knownd. None of the above

11. In present day measurement systems

a. Direct methods are commonly used*b. Use of direct methods is limited but indirect methods are commonly used

c. Both direct and indirect methods are commonly used

d. All of the above

12. In an intelligent information system used for the measurement of a physical quantity

*a. The digital computer must perform all or nearly all the signals and information processing

b. The observer must perform all or nearly all the signals and information processingc. The digital computer is required

d. None of the above

13. In a generalized measurement system, the function of the signal manipulating element is to

*a. Change the magnitude of the input signal while retaining its original identity

b. To perform linear operations like addition and multiplication

c. To perform non-linear operations like filtering, chopping and clipping and clamping

d. None of the above.

14. A modifying input to a measurement system can be defined as an inputa. Which changes the I/po/p relationship for desired inputs only

*b. Which changes the I/po/p relationship for desired as well as interfering inputs.

c. Which changes the I/po/p relationship for interfering inputs only


15. Purely mechanical instruments cannot be used for dynamic measurements because they have

a. High inertia

b. Large time constant

c. Higher response time*d. All of the above

16. The usage of electronic instruments is becoming more extensive because they have

a. A high sensitivity and reliability

b. A fast response and compatibility with digital computersc. The capability to respond to signals from remote places



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17. In a measurement instrument which of the following characteristics is essential?a. Zero Drift

*b. Accuracy

c. Static Error

d. Loading effect

18. In a measurement system which of the following are undesirable characteristics

a. Sensitivity and Accuracyb. Reproducibility and Linearity

*c. Drift, static error, dead zone and loading effect

d. Accuracy and hysteresis

19. A pressure measurement instrument is calibrated between 10 bar and 250 bar.

What is its scale span?

a. 10barb. 250bar

*c. 240bar

d. 260bar

20. Accuracy is

a. True value

*b. Closeness to true valuec. Precise value

d. Exact value

21. Which of the following sentence is acceptable?

*a. A process can be accurate as well as precise

b. A process may not be accurate but can be precise

c. A process may be accurate but not precise

d. All of the above

22. Loading effect occurs mostly at*a. detectortransducer stage

b. Intermediate transducer stage

c. Signal conditioning stage

d. Data presentation stage

23. Hysteresis in a system arises due to the fact that all the energy put into the stressed parts when loading

a. Is recoverable upon unloading

b. Is recoverable upon loading

*c. Is not recoverable upon unloadingd. Remains constant

24. Deflection factor is the ratio of

a. Change in output to change in input

*b. Change in input to change in outputc. None of the above

d. A and B both


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25. Linearity is when*a. Output is linearly proportional to input

b. Output is inversely proportional to input

c. Input is linearly proportional to output

d. Input is inversely proportional to output

26. Reproducibility considers measurement when there is

a. Change in method of measurementb. Change in measuring instrument

c. Change in ambient conditions


27. Accuracy as percentage of scale range can be expressed when

a. Scale multiplier is not a fixed constant

b. Scale range is largec. Scale span is large

*d. Scale range is uniform

28. Static error is defined asa. Ratio of measured value to true value

b. Ratio of true value to measured value

*c. Difference between measured value to true valued. Difference between true value to true value

29. static Correction is given asa. Ratio of static error to true value

b. Ratio of true value to measured value

c. Difference between measured value and true value

*d. Difference between true value and measured value

30. Relative static error is defined as

a. Ratio of static error to true value*b. Ratio of absolute error to true value

c. Difference between measured value and true value

d. Difference between true value and true value

31. Characteristics which vary with time are

*a. Dynamic Characteristics

b. Static Characteristics

c. Static Calibration

d. None of the Above

32. The incapability of a measurement system to faithfully measure, record, or control the input signal inundistorted form is called

a. Threshold

b. Hysteresisc. Zero drift

*d. Loading effect


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33. Largest change of input quantity for which there is no output change is calleda. Dead time

b. Threshold

*c. Dead zone


34. The minimum value of input below which no change in output is detected is

a. Hysteresis*b. Threshold

c. Static error

d. Point accuracy

35. The magnitude of the impedance of an element connected across the Signal Sourse is called

*a. Input impedance

b. Output impedancec. Equivalent impedance

d. Generalized impedance

36. Drift that occurs only over a portion of span of an instrument is calleda. Zero drift

b. Span drift

*c. Zonal driftd. Combined zero and span drift

37. If there is proportional change in the indication all along the upward scale it isa. Zero drift

*b. Sensitivity drift

c. Zonal drift


38. Distortion of original signal may take the form of

a. Attenuationb. Waveform distortion

c. Phase shift


39. Extraction of energy from a system results due to

a. Insertion of primary elements

b. Insertion of auxiliary elements

*c. Insertion of both primary and auxiliary elements


40. The non-coincidence of output when the input is increased and then decreased is on account of?*a. Internal friction or hysteresis damping

b. No friction

c. External frictiond. Internal as well as external friction


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41. which type of measurement is used as a design tool in research and developement areas.*a. Mechanics type

b. Power type

c. Dynamic type

d. Static type

42. Direct method of measurement incorporates

*a. Zero translationb. One Translation

c. Two translation

d. b and c both

43. Which measurement instrument is an example of Secondary Indirect measurement?

*a. Thermometer

b. Bourdons tube Pressure Gaugec. Meter Rod

d. Steel rule

44. Which measurement instrument is an example of Tertiary measurement?a. Vernier Caliper

b. Steel rule

c. Thermometer*d. Bourdons Tube Pressure Gauge

45. Which measurement instruments are so constructed that the quantity being measured can only be measuredby observing the output indicated by the instrument?

a. Absolute Instruments

b. Direct Istruments

c. A and b both

*d. Secondary Instruments

46. Signal that vary in descrete steps and take up finite number of values in any given range are called?*a. Digital Signals

b. Analog Signals

c. Independent Signals

d. Dependent Signals

47. Reproducibility is

a. Point Accuracy

b. Closeness to true value

*c. Closeness to output for same inputd. Exact value

48. Which Instruments are very reliable for Static and Stable conditions.

*a. Mechanical Instruments.

b. Electrical Instruments.c. Electronic Ihnstruments.

d. Electromechanical Instruments.


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49. Absolute measurement instrument use which method of measurement*a. Direct Method

b. Indirect Method

c. Power type measurement

d. mechanics type measurement

50. A transducer is defined as a device which converts

a. A analog signal into digital signal*b. A physical quantity into an electrical signal

c. Measurand quantity into response


51. Gearing arrangement in a Bourdon's Tube Pressure gauge acts as

a. Data transmission element

b. Data presentation element*c. Signal conditioning element

d. Variable Conversion element

52. When the elements of an instrument are actually physically seperated, the data is transmitted through*a. Data transmission element

b. Primary sensing element

c. Variable manipulation elementd. Indicating element.

53. For a digital transmission systema. Analog signals are preffered

*b. Digital Signal are preferred

c. Interfering inputs are preffered

d. Opposing inputs are preffered

54. Non-coincedence of loading and unloading curves is

a. signal distortionb. Attenuation

c. Phase shift

*d. Hysteresis

55. Generalized input impedance is defined as the ratio of

a. Undisturbed value to Trough variable

b. Across Variable to Through variable

c. Measured Value to across variable

*d. Through variable to across variable

56. Threshold occurs due to*a. Input Hysteresis

b. Loading Effect

c. Output Hysteresisd. Backlash


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57. Characteristics which involve use of differential equations area. Primary Characteristics


*c. Dynamic characteristics

d. Absolute Characteristics

58. Which Instruments are very reliable for Static and Stable conditions.

a. Electronic Ihnstruments.b. Electrical Instruments.

*c. Mechanical Instruments.

d. Electromechanical Instruments.

59. For a thermometer having a caliberation of -40 degree celcius to 400 degree celcius, scale span is

a. 400 degree celcius

b. 40 degree celcius*c. 440 degree celcius

d. 360 degree celcius

60. Characteristics which involve use of differential equations are*a. Dynamic characteristics


c. Primary Characteristicsd. Absolute Characteristics

61. Threshold occurs due toa. Loading Effect

*b. Input Hysteresis

c. Output Hysteresis

d. Backlash

62. Generalized input impedance is defined as the ratio of

*a. Through variable to across variableb. Across Variable to Through variable

c. Measured Value to across variable

d. Undisturbed value to Trough variable

63. Variable manipulation element and data presentation element are together called as

a. Signal conditioning stage

b. Detector transducer stage

c. Variable convertion stage

*d. Intermediate stage

64.Static error is equal to*a. absolute static error

b. relative static error

c. static correctiond. deflection factor


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65. Accuracy as percentage of scale range can be expressed whena. Scale multiplier is not a fixed constant

*b. Scale range is uniform

c. Scale span is large

d. Scale range is large


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Unit 3.Detector Tr ansducer1.A transducer converts

a.mechanical energy into electrical energyb.mechanical displacement into electrical signal

*c.one form of energy into another form of energy

d.electrical energy into mechanical form

2.An inverse transducer converts

*a.electrical energy into any other form of energy

b.electrical energy to light energyc.mechanical displacement into electrical signal

d.electrical energy to mechanical form

3.One of the following can act as an inverse transducer

a.electrical resistance potentiometer

b.L.V.D.T.

c.Capacitive transducer*d.piezoelectric crystals

4.One of the following is an active transducer

a.strain gaugeb.selsyn

*c.photovoltaic cell

d.photo emissive cell

5.A strip chart recorder is

a.an active transducer

b.an inverse transducerc.an output transducer

*d.an inverse and output transducer both

6.In a transducer, the experimentally obtained transfer function is different from the theoretical transfer

function, the errors result from this difference are called

a.zero errorb.sensitivity error

*c.non-conformity error

d.hysteresis error

7.A transducer has an output impedance of 1 kilo-ohm and the load resistance is 1 Mega-ohm,the transducer

behaves as

a.a constant current source*b.a constant voltage sourcec.a constant power source

d.none of the given options

8..A transducer has an output impedance of 1 kilo-ohm and the load resistance is 1 ohm,the transducer behaves

as

*a.a constant current sourceb.a constant voltage source

c.a constant power source


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9.In a transducer,the observer output deviates from the correct value by a constant factor the resulting error is

called

a.zero error

*b.sensitivity errorc.non-conformity error

d.hysteresis error

10.The lower limit of useful working range of transducer is determined by

a.mimimum useful input level

*b.by transducer error and noisec.cross sensitivity

d.dynamic response

11.A resistanbe potentiometer is aa.first order instrument

*b.zero order instrument

c.secondorder instrument


12.In a resistance potentiometers, the non-linearity

a.increases with increase of load to potentiometer resistance*b.decreases with increase of load to potentiometer resistance

c.in not dependent upon load to to potentiometer resistance


13.In wire wound strain gauges,the change in resistance on application of strain is mainly due to

a.change inlength of wire

b.change in diameter of wire

*c.change in both length and diameter of wired.change in resistivity

14.Unbonded strain gauges are

*a.exclusively used for transducer applications

b.exclusively used for stress analysis

c.commonly used for both transducer applications as well as for stress analysisd.none of the given options

15.Metal foil type of strain gauges are superior to wire wound metal strain gauges because

a.they have a higher heat dissipation capacity

b.they have a larger surface area which makes bonding easierc.they can be fabricated economically using techniques which are similar to those used for fabrication of micro-

electronic circuitry*d.all of the given options

16.Metal foil gauges use fat end turns in order to*a.reducetransverse sensitivity

b.reduce lomgitudinal sensitivity

c.reduce cross sensitivityd.all of the given options


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17.In a semi-conducter strain gauges, the change in resistance on application of strain is mucha.higher than that of metal strain gauges and this is mainly due to change in dimensions

*b.higher than that of metal strain gauges and this is mainly due to change in resistivity

c.lower than that in the case of metal strain gauges

d.none of thegiven options

18.The RTDs use the principle of change of resistance with temperature.The properties of a conducter material

to be used as an element of an RTD should possess the following propertiesa.the change in resistance per unit change in temperature should be as small as possible

b.the resistance of the materials should not have a continous and stable relationship with temperature

c.the change in resistance with temperature should not be a linear function*d.none of the given options

19.Platinum is the commonly used metal for RTDs because

a.platinum has a constant value of resistance temperature co-efficient of 0.004/degree celcius for a temperaturerange between 0 to 100 degree celcius

b.the resistivity of platinum tends to increase less rapidly at higher temperatures

c.platinum is available in pure form for commercial applications and has a stability over higher ranges of

temperature*d.all of the given opyions.

20.The sensitivity of thermistors as compared with sensitivity of platinum RTD over a temperature range of -100 to 400 degreecelcius to changes in temperature is

a.100 times

*b.10^6 timesc.10^7 times

d.10^3 times

21.A thermister exibits

a.only a negative change of resistance with increase in temperatureb.only a positive change of resistance with increase in temperature

*c.can exibit a negative or positive change of resistance with increase of temperature depending upon the typeof material used


22.The temperature transducers exibit non-linear behaviour.The order in which they exibit nonlinearity(highestto lowest) is

a.thermocouples, RTD, Thermistors

*b.thermistors, thermocouples, RTDs

c.RTDs, thermocouples. thermisters

d.thermistores, RTDs, thermocouples

23.Three types of temperature transducers are compared as regards their sensitivity.The order in which theyexhibit their sensitivities (highest to lowest) is

*a.thermistors, RTDs, thermocouples

b.thermocouples, RTD, Thermistorsc.RTD, Thermistor,thermocouples

d.RTDs, thermocouples. thermisters


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24.Thermocouples area.passive transducers

*b.active transducers

c.both active and passive transducers

d.output transducers

25.Thermocouples

a.are most commonly used temperature transducersb.require reference junction compensation

c.have a low output voltage level

*d.all of the given options

26.Air cored inductive transducers are suitable for use

a.at lower frequencies

*b.at higher frequenciesc.at equal frequencies

d.as are employed for iron cored transducers

27.The size of air cored transducer as compared with their iron cored counterparts isa.smaller

*b.bigger

c.samed.all of the given options

28.Inductive transducers are used in differential configuration because the output is not influenced bya.external magnetic fields

b.temperature changes

c.variations of supply voltage and frequency


29.In an L.V.D.T, the two secondary windings are connected in differential to obtain

a.higher output voltageb.an output voltage which is phase sensitive i.e. the output voltage has a phase which can lead us to a

conclusion whether the displacement of the core took place from left to right

c.in order to astablish the null or the reference point for the displacement of the core


30.In LVDT core is made up of a

a.non-magnetic material

b.a solid ferro-electric material

*c.high permeability, nickel-iron hydrogen annealed material in order to produce low harmonics,low nullvoltage and high sensitivity.the core is slotted to reduce eddy current losses

d.allof the given options

31.An LVDT

a.Exibits linear characteristics upto a displacement of +- 5mmb.has a linearity of 0.05%

c.has an infinite resolution and a high sensitivity which is of the order of 40 V/mm



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32.An LVDta.has very good frequency response as the mass of the core to which the input signal is applied,is fairly large

b.is immune to stray magnetic fields

c.has a zero voltage at the null point even if the supply voltage contains and harmonics and even if the two

secondary windings are not exactly similar and even assymmetrically placed with respect to primary windings*d.none of the given options.

33.Capacitive transducers are normally used fora.static measurement

*b.dynamic measurement

c.both static and dynamic measurementd.transient measurement.

34.The dynamic characteristics of capacitive transducers are similar to those of

a.low pass filters*b.high pass filters

c.notch filters

d.band stop filters

35.A capacitive transducer working on the principle of change of capacitance with change of displacement,

exibits non-linear characteristics.the response of these transducers can be made linear by using

a.differential arrangementb.use of an OPAMp(operational amplifier)

*c.working them over a small displacement range

d.all of the given options

36.Capacitive transducer can be used for measurement of liquid levels.the principle of operation used in this

case is

a.change in capacitance with change of distance between plates

b.change of area of plates*c.change of dielectric strength


37.What is the order of minimum displacement that can be measured with capacitive transducer?

a.1 cm

b.1 mm*c.1 um

d.1x10^-12 m

38.The capacitive transducer have a high output impedance and, therefore,

a.to reduce loading effects long lengths of cable should be usedb.to increase the value of resonant frequency long lengths of cables should be used

c.long cable lengths should be used in conjunction with capacitive transducers in order to improve theirfrequency response

*d.none of the given options

39.Ceramic materials are used for piezoelectric transducers

a.they are polycrystalline in nature

b.they are basically made of barium titanatec.they do not have piezo-electric properties in their original state but these properties are produced by special

polarizing treatment


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40.Quartz and Rochell salt belong to

*a.natural group of piezo-electric materials

b.synthetic group of piezo-electric materials

c.can belong to natural or synthetic group of piezo-elctric materials provided properly polarizedd.all of the given options

41.Piezo-elctric transducers area.passive transducers

b.active transducers

c.inverse transducers*d.active and inverse transducers

42.A photvoltaic cell is connected across a very large value of resistance, its sensitivity at higher illumination

levels is typicallya.infinity

b.zero

c.some finite value which is very large

*d.some finite value which is very small and nears zero

43.Which of the following photo-electric devices is most suitable for digital applications

a.photo-emmisive cellb.photo-diode

c.photo transistor

*d.photo-voltaic cell

44.Which of the photo-electric trabsducer is used for production of elctric energy by converting solar energy

a.photo-emmisive cell

b.photo-diode

c.photo transistor*d.photo-diode and photo transistor

45.Which of the following optical transducers is an active transducer

a.photo emissive cell

b.photo diode

c.photo transistor*d.photo voltaic cell

46.A cadmium sulphide cell has the highest response for a light of wavelength of mearly

a.300 mm

b.800 mm*c.500 mm

d.600 mm

47.A photo diode function as

*a.photo conductive device while working with reverse voltageb.photo voltaic device while working without a reverse voltage

c.photo voltaic device while working with or without a reverse voltage


48.The photo diode as compared to a transistor has


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a.faster switching time

b.lower sensitivityc.higher size for the same value of output current


49.A photoconduvtive cell is useful fora.high frequency applications

b.medium frequency applications

*c.low frequency applicationd.all of the given options

50.A linear displacement transducer (digital) normally usesa.straight binary code

b.BCD

*c.Gray code

d.Hexadecimal code

51.A tachometer encoder can be used for measurement of displacement

a.in both the directions

*b.in only one directionc.its output pulses are counted only for the forward direction

d.its output pulses are counted only for the reverse direction

52.Incremental counters use

a.one channel

b.two channels*c.two channels and sometimes three


53.Absolute Encoders are used for

*a.normally one revolutionb.continous speed

c.continous speed in both the directionsd.none of the given options

54.Absolute encoders are used where

a.fast varying signals are not usedb.when position data is to be recovered even after a temporary power outage

c.transient noise can be tolerated as it causes only a transient disturbance


55.Moire Fringes are used for measurement of rotary displacement along witha.only contact type encoders

*b.only optical encodersc.both contact type and optical encoders



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Uni t. 5.Methods of measurement

a.Pressur e Measur ement

1.Bellows type of pressure gauges have the advantage of

*a.they can be used for low,medium and high pressuresb.they can be used for measurement of dynamic pressures

c.they do not need any temperature compensating devicesd.drift and hysteresis allow their use in applications having +-2% of full span accuracy

2.The disadvantages of strain gauge pressure transducer are

a.They have a poor frequency response

b.They do not have a continous resolutionc.They cannot be powered by a.c. sources

*d.They have a low output

3.Which of the following types of Bourdon tube shapes has a small tip travel and nevessitates amplification?*a.C-type

b.Spiralc.Helical shapedd.round

4.Manometers measure unknown pressure by

a.measuring liquid levelsb.measuring height of liquid columns

*c.balancing the unknown force produced by pressure against a known force

d.noting the deflection of a pointer

5.In thermal conductivity gauges,the major source of error is heat lost on account of

*a.radiationb.conductionc.convection

d.both conduction and reduction

6.The desirable property of manometric fluid is

a.High viscosity

b.high co-effecient of thermal expansion*c.low vapour pressure

d.corrosiveness and sickness

7.The advantages of manometer are*a.higher accuracy,repeatibility,wide range of filling liquids and their ability to work as primary standards

b.fragility and probability

c.ability to work in hazardous environments

d.ability to work under all conditions and at all altitudes

8.Piezometer is used for measuring

*a.gauge pressureb.vaccum

c.absolute pressure

d.pressure differences between two fluids


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9.A U-tube differential manometer is used inverted when*a.pressure difference is small

b.pressure difference is large

c.cannot be used inverted

d.no pressure difference

10.A typical piezoelectric pressure transducer has a range of

a.0 to 10 kpab.0 to 100 kpa

c.0 to 700 kpa

*d.0 to 20 kpa

11.In thermocouple gauges, the temperature of heated strip lies between

a.0 to 100 degree celcius

*b.50 to 400 degree celciusc.200 to 1000 degree celcius

d.10 to 50 degree celcius

12.In order to avoid errors on account of changes in ambient temperature Pirani gaugesa.are enclosed in temperature controlled chambers

*b.use one active and one dummy element

c.use bridge measuring circuitsd.none of the given options

13.Vaccum pressure isa.equal to gauge pressure

b.equal to atmospheric pressure

*c.lower than atmospheric pressure

d.equal to absolute pressure

14.Velocity pressure is difference between

a.dynamic pressure and static pressure*b.stagnation pressure and static pressure

c.impact pressure and dynamic pressure

d.impact pressure and stagnation pressure

15.A well-type manometer is used in preference to a simple U-tube manometer to obtain

a.better accuracy

b.better precision

c.a constant zero

*d.higher sensitivity

16.Which of the following cannot be used for negative pressures*a.piezometer

b.Pirani gauge

c.U-tube manometerd.Bourdon gauge


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17.The accuracy of dead weight tester is affected bya.friction force

b.uncertainity of the value of effective area of piston

c.uncertainity of the value of gravitational constant

*d.all of the given reasons

18.Signal conditioning is carried out by the capillary tubes which convert gas pressure into a mercury

height.This statement pertains toa.bourdon tube pressure gauge

b.pireni gauge

*c.McLeod gauged.diaphragm pressure transducer

19.The angular error in a Bourdon tube refers to

a.pointer or hand becomes loose on the spindleb.gauge tends to give a progressively higher or lower reading

*c.gauge reads correctly both at maximum and minimum readings but gives an inaccurate reading at the mid

point

d.any of the given options

20.McLeod gauge

a.can be used for pressure below 0.1x10^-3 torrb.gives continous output

*c.is sensitivity to condensed vapours that may be present in the sample of the gas whose pressure is being

measuredd.cannot be used as standard for vaccum measurement

21.Inductive pressure transducer

a.have poor dynamic response

*b.have high sensitivityc.are sensitive to vibrations

d.none of the given option

22.Pressure transducer using LVDT have

*a.poor dynamic response

b.linear response over a large rangec.low sensitivity


23.Unit of Vaccum pressure is

a.barb.N/m^2

*c.torrd.kg/cm^2

24.At standard conditions One torr is equal toa.10 mm of Hg

b.760 mm of Hg

c.-1 mm of Hg*d.1 mm of Hg


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25.Which is the odd man out from belowa.Pirani gauge

b.Thermal conductivity gauge

*c.Bourdon tube pressure gauge

d.Piezoelectric pressure gauge

26.Elastic pressure elements are used for measurement of very high pressures upto about

a.1000 MN/m^2*b.700 MN/m^2

c.1000 N/m^2

d.100 N/m^2

27.Disadvantage of Bourdon tubes are

*a.low spring gradient

b.elliptical cross-sectionc.sector-pinion mechanism

d.high sring gradient

28.Arc of C-type Bourdon tube isa.150 degree

*b.250 degree

c.50 degreed.180 degree

29.The absence of geared sector and pinion arrangement in Spiral Bourdon tube pressure gauge eliminatesa.Hysteresis

b.drift

*c.backlash

d.static loading

30.The minimum and maximum number of coils employed in Helical BOURDON TUBE PRESSURE GAUGE

area.1 and 10+

b.12 and 40+

c.9 and 11+

*d.3 and 16+

31.Bellows used in pressure gauges are

a.tough and made by machining

*b.seamless and made from drawn tubing by hydraulic or other methods of rapid forming

c.welded togetherd.used for temperature measurement

32.Which of the following type of mechanical transducer have caliberated spring

a.Bourdon tubes

b.manometersc.diapragms

*d.bellows


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33.Bellows are filled with liquids likea.ethyl alcohol

*b.ethylene glycol or water

c.brine solution

d.mercury

34.As the pressure of gas becomes smaller and smaller , the mean free path of the molecules becomes

a.slowb.small

c.null

*d.greater

35.Average distance a molecule travels between collisions is called

a.dead zone

b.lead time*c.mean free path

d.pertinent dimension

36.The temperature of the heated strip lies between*a.50 to 400 degree celcius

b.100 to 400 degree celcius

c.1 to 100 degree celciusd.0 to 400 degree celcius

37.Dead weight tester isa.pressure measurement instrument

*b.pressure gauge calliberation instrument

c.weight measurement instrument

d.force measurement instrument

38.Vaccum pressure gauges are used to measure

*a.pressure below atmospheric pressureb.only atmospheric pressure

c.pressure above atmospheric pressure

d.pressure below 10 kg/cm^2

39.Most commonly used crystal for piezoelectric transducer is

a.ceramic

b.lead

c.dipotassium tartarate

*d.Quartz

40.Materials used for Diaphragm includea.Rochell salts and Quartz

b.ceramics

*c.phospor bronze and stainless steels beryllium copperd.lithium sulphate


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b. Temperature Measurement

1.In pressure thermometers when mercury is used, the bulb capillary should be made ofa.copper

b.alloys of copper

*c.stainless steel

d.none of the above

2.Partial immertion Liquid-in-glass thermometers give errors because

a.thermometer is not fully immerersedb.the temperature of the emergent portion is higher than that of the immersed portion.

c.the temperature of the emergent portion is lower than that of the immersed portion.

*d.the temperature of the emergent portion is different from that of the immersed portion.

3.Mercury is used in liquid filled thermometers as it gives

a.wide temperature range

b.high sensitivity*c.wide temperature range and approximately linear scale

d.wide temperature range and high sensitivity

4.For the same temperature range, the volume of bulb of a gas filled thermometer is,*a.greater than that of a liquid filled or a vapour filled thermometer

b.smaller than that of a liquid filled or a vapour filled thermometer

c.greater than that of a liquid filled but lesser than that of vapour filled thermometerd.lesser than that of a liquid filled but greater than that of vapour filled thermometer

5.In filled systems used for temperature measurement, full compensation is used for compensating for effect of

a.changes in ambient temperature, head and baromeric pressureb.changes in ambient temperature, where the receiving element is located

*c.changes in ambient temperature, where both the receiving element and the capillary tube are located.d.all of the above

6.RTD's present no problem in measurement of temperature because

a.there are no errors caused by resistance of leads when the resistance of elements is measured.b.they have a robust construction

c.there are no self-heating effects when using them

*d.none of the given options

7.Semi-conductor thermomrters have the disadvantage that they

a.are not readily available and are expensive

b.are fragile and have low sencitivityc.are large in size and have a poor frequency response*d.none of the given options

8.The advantages of thermistor area.resistance of thermistor is high and therefore error due to resistance of leads is negligible

b.errors due to self-heating are small

c.their sensitivity is about 10^6 as high as that of plat6inum resistance thermometers.*d.all of the above


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9.Law of intermediate metals in thermocouples allows them to

a.use reference junction compensationb.use meters for measurement of emf without disturbing the circuit conditions

c.use extension wires of materials other than the ones used for making thermocouples

*d.use of both, meters as well as extension wires

10.Thermopile is

*a.a combination of a number of thermocouples connected in series

b.a combination of a number of thermocouples connected in parallelc.a combination of a number of thermocouples some of which are connected in series and some in parallel

d.a combination of a number of thermocouples connected neither in series nor in parallel

11.Reference junction compensation in thermocouple can be provided through use of

a.hardware only

b.software only

*c.both hardware and softwared.neither harware nor software

12.The probes used for measurement of high speed flows measure

*a.recovery temperatureb.stagnation temperature

c.static temperature


13.Radiation pyrometers are used in the temperature range of

a.0 to 500 degree celciusb.500 to 1000 degree celcius

c.-250 to 500 degree celcius

*d.1200 to 2500 degree celcius

14.Which of the following units are employed where it is not possible to have a physical contact with thesystem whose temperature is to be measured?

a.thermocouplesb.resistance thermometers

*c.resistance pyrometers

d.thermister

15.A parallel combination of thermoouples is used for measurement of

a.small temperature differences between the two junctions

b.large temperature differences between the two junctions

*c.average temperature of a number of points


16.In presuure thermometers when mercury is used, the bulb and capillary should be made ofa.copper

b.alloys of copper

*c.stainless steeld.rubber

17.Partial immersion liquid-in-thermometers give errors becausea.thermometer is not fully immersed

b.the temperature of the emergent portion is higher than that of the immeresed portion


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c.the temperature of the emergent portion is lower than that of the immeresed portion

*d.the temperature of the emergent portion is different than that of the immeresed portion

18.Recording is not possible with

*a.liquid-in-thermometers

b.thermocouplesc.filled in system thermometers


19.Which metal/non-metal has the highest temperature range?

a.semiconductor

b.nickelc.copper

*d.platinum

20.which arrangement has the null-balance operation?*a.optical pyrometer

b.resistance thermometer

c.liquid-in-glass thermometer

d.bimetallic thermometer

21.In filled systems used for temperature measurement,full compensation is used for compensating the effect

of?a.changes in ambient temperature,head and barometric pressure

b.changes in ambient temperature where the receiving element is located

*c.changes in ambient temperature where both the receiving element & the capillary tube are locatedd. all of the given options

22.The electrical output from a thermocouple circuit is detected by using

a.Wheatstone bridge

b.current sensitive device*c.voltage-balancing circuit

d.RTD

23.Which arrangement has the capability to measure the temperature of an object which may be either

stationary or moving?

a.thermocoupleb.thermister

*c.Total radiation pyrometer

d.filled-in-system thermometer

24.Self-compensating capillary tube is used in the filled-in-thermometer to eliminate or minimizea.elevation effect

b.immersion effectc.barometric effect

*d.temperature effect

25.Mercury is used in liquid-in-filled systems as it gives

a.wide temperature range

b.high sensitivity*c.wide temperature range and approximately linear scale

d.wide temperature range and high sensitivity


25/38

26.In which thermometers; liquids,gases and vapours can all be useda.liquid in thermometers

b.bimetallic thermometers

*c.pressure thermometers

d.gas filled thermometers

27.Radition Pyromrter have

*a.high speed responeb.high surface response

c.moderate speed response

d.low speed response

28.A device which measures total intensity of radiation emitted from a body is called

a.thermister

b.Resistance temperature detectorc.bimetallic thermometer

*d.Radion Pyrometer

29.Thermistors havea.high speed respone

*b.fast thermal response

c.slow surface responsed.moderate thermal response

30.The gases used in gas thermometers area.neon and argon

*b.nitrogen and helium

c.oxygen and helium

d.nitrogen and argon

31.Seebeck effect is

*a.reversible in natureb.irreversible in nature

c.constant

d.stable

32.The resistance element response time is of the order of

*a.2 to 10 seconds, depending on construction

b.15 to 20 seconds, depending on construction

c.0 to 10 seconds, depending on construction

d.90 to 120 seconds, depending on construction

33.The reponse of thermometer becomes faster ifa.partial area of bulb is exposed to the process fluid

b.point contact of bulb with the process fluid

c.no contact of bulb with process fluid*d.greater area of bulb is exposed to the process fluid

34.thermisters havea.low and positive temperature coefficient

b.high and positive temperature coefficient


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c.low and negative temperature coefficient

*d.high and negative temperature coefficient

35.Absolute temperature is equal to

a.thermometer reading in degree celcius

*b.thermometer reading in degree celcius plus 273.15c.thermometer reading in degree celcius plus 760 mm of Hg

d.thermometer reading in degree celcius plus 273

36.When mercury is used in liquid-in-thermometer, temperature range for thermometer is

*a.-38.9 to 600 degree celcius

b.-130 to 36 degree celciusc.-100 to 78 degree celcius

d.-92 to 110 degree celcius

37.Bimetallic thermometers are made with metals which havea.small difference in thermal expansion coeffients

b.negligible difference in thermal expansion coeffients

c.no difference in thermal expansion coeffients

*d.widely different thermal expansion coeffients

38.The electrical output from a RTD circuit is detected by using

*a.Wheatstone bridgeb.current sensitive device

c.voltage-balancing circuit

d.ammeter

39.Mercury is generally used in

a.low grade thermometers

b.ambient grade thermometers

*c.High grade thermometersd.medium grade thermometers

40.low grade thermometers use

a.mercury

b.invar

c.copper*d.ethyl alcohol,pentane and toluene


27/38

c.Force and Torque Measur ement1.The term "method of symmetry" is used for

a.measurement of weight by equal arm balances*b.checking of two sides of an equal arm balance for identical conditions on two sides of balance

c.checking of two sides of an un-equal arm balance for identical conditions on two sides of balance


2.In a balance with multi-lever system the unknown weight may be placed

a.at any position on the platform and it will not effect the result

b.at a particular position on the platform to get proper results*c.at any position on the platform subject to certain conditions and it will not affect the result

d.at centre and it will affect the result

3.In an equal arm balance the buoyancy effects

*a.cause lesser error if the unknown weights are made of materials having high density

b.cause greater error if the unknown weights are made of materials having low density

c.are independent of the density of materialsd.are independent of the weight of materials

4.Eletromagnetic type of balances

a.are more sensitive to environmental effects*b.give an output which can be used for display,recording and control

c.are of large size and have slow response

d.cannot be operated from a remote location

5.Hydraulic load cells are available which have a maximum capacity of

a.10 KN

b.50 KNc.10 MN

*d.50 MN

6.Pendulum type of scales used for measurement of force work on the principle of

a.comparing the unknown force with a known force

b.converting the unknown force to power and cmparing it with known power*c.converting the unknown force to torque and cmparing it with known torque


7.Elastic elements used for measurement of force givea.high sensitivity and slow response if they are stiff

*b.low sensitivity and fast response if they are stiff

c.low sensitivity and slow response if they are stiffd.low sensitivity and zero response

8.Piezoelctric type load cells can be used for measurement of

a.dynamic forces onlyb.dynamic forces and static forces provided the load cells have a small time constant

*c.dynamic forces and static forces provided that the load cells have a large time constant

d.static forces only


28/38

9.Torque of a rotating shaft is measured by mounting a strain gauge bridge on the shaft.The supply to the bridge

circuit is given to it and the output from it is taken from by usinga.only slip rings

b.only rotary transformers

*c.slip rings,rotary transformers,telemetry equipement


10.Unit of torque is

*a.N-mb.N/m

c.N

d.N/m^2

11.Unit of force is

a.N-m

b.N/m*c.N

d.N/m^2

12.Standard for force depends on standards of*a.mass and acceleration

b.mass and velocity

c.pressure and loadd.mass and pressure

13.Which device is used for torque measurement being exerted along the rotating shaft so as to determine shaftpower

a.Tachometer

b.Stroboscope

*c.Dynamometer

d.Scales

14.A sink isa.A transmission dynamometer

b.A driving dynamometer

*c.An absorption dynamometer

d.Any Dynamometer

15.When the combination of strain gauge-elastic member is used for weighing, it is called

a.Dynamometer

*b.Load Cell

c.Bridge Circuitd.None of the given options

16.The proving rings are steel rings used as

a.velocity stantards

b.pressure standards*c.Force standards

d.temperature standards


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17.The use of which scales(weighing balance) requires that the force should be steady for 2 to 3 seconds for the

scale to come to resta.Equal arm balance

*b.Pendulum balance

c.digital balance


18.Pneumatic load cell operates on

*a.force-balance methodb.pressure-balance method

c.mass-balance method

d.weight-balance method

19.In which torsion meter the angular deflection of a parallel length of shaft is used to measure torque

a.Electrical tortion meter

b.straingauge tortion meterc.Optical tortion meter

*d.Mechanical tortion meter

20.In which tortion meter four bonded-wires are mounted on a 45 degree helix with the axis of rotation; and areplaced in pairs diametrically opposite

a.Electrical tortion meter

*b.straingauge tortion meterc.Optical tortion meter

d.Mechanical tortion meter

21.Which tortion meter system uses two photoelectric or magnetic transducers, where a measure of time

between pulses from two slotted disc generates a signal which is proportional to the angular twist theta

*a.Electrical tortion meter

b.straingauge tortion meter

c.Optical tortion meterd.Mechanical tortion meter

22.For which load cell, on application of force the liquid pressure increases and equals the force magnitude

divided by the effective area of the diaphragm

a.Strain guage load cell

b.Pneumatic load cell*c.Hydraulic load cell


23.The strain-guage load cell find extensive use in

a.Road vehicle weighing devicesb.Draw ber and tool-force dynamometers

c.Crane load monitoring*d.all of the given options

24.The use of foer identical strain gauges in each arm of the bridge provides full temperature compensation andalso increases the sensitivity of the bridge by

*a.2(1+u) times

b.4(1+u) timesc.2(4+u) times

d.(1+u) times


30/38

25.Which scale is used for spring-testing devices because its accuracy permits tasting a wide range of springs

with high accuracy

a.Pendulum scale

b.even-arm scalec.weighing maching

*d.pendulum scale


31/38

d.F low Measurement1.Which of the following meter is used for measuring flow of clean fluids only?

a.Ultrasonic flow meter

b.Turbine Flow meterc.Laser doppler anomometer

*d.Hot wire anemometer

2.Which of the following flow meters is capable of measuring the rate of flow as well as totalized flow?a.Nutating disc flow meter

b.Electromagnetic flow meter

c.orifice meter*d.Lobed impeller flow meter

3.Annubar tubes can be used for measurement of flow rates ofa.liquids only

b.gases only

c.liquids and gases

*d.liquids,gases and steam

4.The meter which is suitable for flow totalization is*a.turbine meter

b.venturimeterc.ultrasonic flow meters

d.orifice plate

5.The fluid flow between the electrodes of an electromagnetic flow meter generates an e.m.f which is a function

of

a.dynamic pressure

b.discharge*c.flow velocity

d.all ot the given options

6.The size of venturimeter is expressed as 300x150 mm. it means that

a.the diameter of the upstream pipe is 300mm and that of downstream pipe is 150mm

*b.the diameter of the pipe is 300mm and that of throat is 150mmc.the diameter od pipe is 150mm and that of throat is 300mm

d.none of the given opions

7.Venturimeters havea.High head loss, low co-efficient of discharge and small size

b.low head loss, low co-efficient of discharge and small size

c.low head loss, low co-efficient of discharge and large size*d.low head loss, high co-efficient of discharge and large size

8.In an ultrasonic flow meter, the error caused by velocity of sound propogation in medium can be eliminated

bya.measuring transit time

b.measuring phase shift

c.measuring difference of transit times in the direction of flow and against the direction of flow*d.measuring difference of frequency in the direction of flow and against the direction of flow


32/38

9.A pitot-static tube measures

a.static pressureb.dynamic pressure

c.total pressure

*d.difference between total and static pressure

10.Which of the following instrument is a rate meter?

*a.Venturimeter

b.Weight meterc.Volumetric

d.Quantity meter

11.A flow meter that measures flow rates which are independent of density is

a.rotameter

*b.variable area flow meter

c.variable head flow meterd.rotating propellor type flowmeter

12.Of the various methods of measuring discharge through a pipeline, the one with the least loss of energy and

direct readings is by means ofa.transversing a pitot statictube

b.oroficemeter

c.notch*d.venturimeter

13.Variable head flow meters can be used for measurement of flow ofa.liquids only

b.liquids and gases

c.slurries only

*d.liquids,gases and slurries

14.Nozzels are useful for measurement of

a.fluids which are cleanb.fluids which are clean and may contain solids

*c.fluids which are clean and may contain solids and also for high pressure/temperature steam

d.fluids which are clean and may contain solids and also corrosive liquids

15.Pitot tubes produce

a.large head loss,produce high differential pressure and have high sensitivity

b.high head loss,produce low-differential pressure and have high sensitivity

c.high head loss,produce low-differential pressure and have low sensitivity

*d.low head loss,produce low-differential pressure and have low sensitivity

16.Rotameter is aa.drag force flow meter

*b.variable area flow meter

c.variable head floe meterd.rotating propellor type flow meter


33/38

17.The specific gravity of the float or bob material should be

*a.Higher than that of the fluid to be meteredb.Lower than that of the fluid to be metered

c.Equal to that of the fluid to be metered


18.When a liquid flows around a pipe bend which rate meter should be used

a.Rotameter

b.Nutating disc meter*c.Elbow meter

d.Current meters

19.A weir, which is esentially a dam with a notched opening at the top through which the liquid flows makes

use of

a.Rectangular notch

b.V-notchc.Tapezoidal Notch

*d.All of the given options

20.Unit of discharge isa.m^2/sec

*b.m^3/sec

c.mm of mercuryd.mm/sec

21.Which type of flow meters basically capture and release a fixed volume of fluid by some type of pumpingaction

*a.Positive displacement flow meter

b.mass measurement meters

c.Inferential rate meters

d.Thermal flow meters

22.Which device used for open flow measurement is an open channel whose sides are arranged sharply to forma throat, followed by a fairly long expansion section.

a.weirs

*b.venturi flume

c.annubar tubed.pitot tube

23.Flow visualisation methods utilize which basic principles for their working

a.introducton of tracer particles

b.detection of changes in optical properties which are related to flowc.add a coloured dye to the liquid


24.Under ordinary conditions ,the transition zone for fluid flow is considered between, when

a.Reynolds number is less than 2000b.Reynolds number is more than 4000

*c.Reynolds number lies between 2000 to 4000

d.Reynolds number is zero


34/38

25.The size of venturimeter is expressed in terms of

*a.inlet and throat diametersb.outlet and throat diameters

c.only trhoat diameters

d.convergent and divergent cone angles


35/38

e.Speed,Velocity and Acceleration measur ement1.Speed is

a.Vector quantity

*b.Scalar quantityc.time per unit distance

d.force per unit distance

2.Velocity is*a.Vector quantity

b.Scalar Quantity

c.Change is accelerationd.force per unit distance

3.Acceleration isa.scalar quantity

*b.change in velocity per unit time

c.change in speed per unit time


4.Unit of velocity isa.m/s^2

*b.m/sc.N-m

d.meter

5.Unit of acceleration is

*a.m/s^2

b.m/s

c.N-md.meter

6.Which measurement instrument either continously indicates the value of rotary speed or continously displaysa reading of average speed over rapidly operated short intervals of time.

a.Accelerometer

b.Dynamometer*c.Tachometer

d.Load Cell

7.Which Tachometers are preferred generally for better outputa.Mechanical

*b.Electrical

c.Hand speed Indicatorsd.Tachoscope


36/38

8.Electromagnetic velocity transducer work on the assumption(s)

a.the current in the exciting coil, if any, is constantb.the current in the exiting coil, if any, is constant and the average value of reluctance is considerably greater

than variations in reluctance

c.the current in the exciting coil, if any, is constant, the average value of reluctance is much greater than

variations in reluctance and the reluctance of iron parts is negligible.*d.the current in the exciting coil, if any, is constant, the average value of reluctance is much greater than

variations in reluctance, the mmf divided by square of reluctance is constant and the reluctance of iron parts is

negligible

9.The sesmic type of velocity transducer can be used for measurement of

a.linear velocity onlyb.acceleration only

*c.linear velocity and acceleration


10.In measurement of linear velocity by Doppler effect radio or ultrasonic beams are used.If the moving object

is travelling towards the receiver

*a.the frequency of the transmitted signal is lower than that of signal received back

b.the frequencies of the transmitted signal and that of the signal received back are equalc.the frequency of the transmitted signal is greater than that of signal received back


11.The mechanical tachometers should be used for measurement of angular speed of

a.small machines having constant speed

b.small machines having variable speedc.large machines having variable speed

*d.of rotating shaft by registering the total number of revolutions per minute during the period of contact

12.Which of the following tachometer is a Mechanical Tachometer

a.Capacitive Tachometer*b.Revolution counter and timer tachometer

c.Stroboscopic tachometerd.D.C.Tachometer

13.Which of the following tachometer is an Electrical Tachometer

*a.Photoelectric tachometerb.Vibrating reed tachometer

c.Tachoscope

d.Centrifugal Tachometer

14.Centrifugal tachometers are suitable to measure speeds uptoa.1000 rpm

*b.40000 rpmc.4000 rpm

d.5000 rpm


37/38

15.Which tachometer employs a timing device and counts the number of revolutions in a measured length of

timea.Drag-cup tachometer

*b.Revolution counter and timer tachometer

c.Capacitive Tachometer

d.A.C.tachometer

16.Which tachometer works on the principle that centrifugal force is proportional to the speed of rotation

a.Hand speed indicatorb.Photoelectric tachometer

c.Eddy current tachometer

*d.Fly-ball tachometer

17.Which tachometer uses a series of consecutively timed steel rods to determine the speed on the basis of

vibrations created by the machine.

*a.Vibrating reed tachometerb.Photoelectric tachometer

c.Drag-cup tachometer

d.capacitive tachometer

18.In a D.C tachogenerator the e.m.f generated depends on

a.field excitation

b.shaft speed*c.field excitation and shaft speed

d.voltage

19.The inherent demerits associated with D.C. tachogenerator are due to provision of

a.Armature

*b.commutator and brushes

c.resistor

d.permanent magnet

20.The number of pulses generated in a photoelectric tachometer depends ona.light source

b.light sensor

c.opaque disc

*d.Number of holes in the opaque disc and shaft speed

21.If the number of holes on the opaque disc of photoelectric tachometer if fixed, the number of pulse generated

will depend only on

a.light source

b.light sensorc.opaque disc

*d.shaft speed

22.Automobile Speedometers operate on the principle of

a.Photoelectric tachometerb.Stroboscopic tachometer

*c.Eddy current od Drag-cup tachometer

d.Capacitive tachometer


38/38

23.Which tachometer cannot be used where ambient lighting is above certain value; for it to be most effective,

the surrounding light must be subdued.*a.Stroboscopic tachometer

b.Centrifugal tachometer

c.Eddy current od Drag-cup tachometer

d.Photoelectric tachometer

24.Which accelerometer can also be used as Vibration sensor

a.Piezoelectric accelerometer*b.seismic accelerometer

c.Both Piezoelectric accelerometer and seismic accelerometer

d.None of the given options

25.Which accelerometer work on the principle of Newton's second law of motion

*a.Piezoelectric accelerometer

b.seismic accelerometerc.Both Piezoelectric accelerometer and seismic accelerometer


26.Which accelerometer senses displacement to give appropriate acceleration outputa.Piezoelectric accelerometer

*b.seismic accelerometer

c.Both Piezoelectric accelerometer and seismic accelerometerd.None of the given options

27.Which accelerometer senses force exerted on mass and crystal to give appropriate acceleration output*a.Piezoelectric accelerometer

b.seismic accelerometer

c.Both Piezoelectric accelerometer and seismic accelerometer


28.D.C tachometer generators are sometimes preffered over A.C. tachometer generators because

a.it is possible to know the direction of rotationb.they present no maintenance problems

*c.it is possible to know the direction of rotation and magnitude of speed with the help of a simple D.C.

voltmeter


29.A seismic transducer working in the displacement mode should be designed to have

*a.weak springs and heavy mass

b.weah springs and light mass

c.stiff springs and heavy massd.stiff springs and light mass

30.The advantage of Drag-cup rotor A.C. tachometer generator are

a.the input voltage to the reference winding meed not be constant

b.the frequency of voltage applied to the reference winding can be very low*c.they are rugged, inexpensive, require little maintenance and a ripple free putput voltage which is linearly

i l h l d

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