EE AND ECE IMPORTANT MCQ PDF-Electrical and Electronics Measurement Part-1

1)   The full range of audibility in audio frequency oscillator is               

a. 0 to 20 Hz
b. 20 Hz to 2 kHz
c. 20 Hz to 20 kHz
d. 20 Hz to 20 MHz
ANSWER: 20 Hz to 20 kHz
2)   A liquid crystal display requires

a. An AC drive
b. A DC drive
c. Both AC and DC drive
d. None of these
  
ANSWER: An AC drive
3)   The detectors used in optical sensors is

a. Photodiodes
b. Phototransistors
c. Laser
d. Only (a) and (b)
e. All the above
    
ANSWER: Only (a) and (b)
4)   Optical sensors used for the displacement measurement works on the principal that

a. Intensity of light increases with distance
b. Intensity of light decreases with distance
c. Intensity of light remains constant with distance
d. Intensity of light increases with time
  
ANSWER: Intensity of light decreases with distance
5)   Capacitance sensor can measure very small displacement. It can be formed by varying

a. Separation
b. Area
c. Permittivity
d. Either (a) or (b) or (c)
  
ANSWER: Either (a) or (b) or (c)
6)   The ionization gauge an instrument used for the measurement of 

a. Very low pressure
b. Medium pressure
c. High pressure
d. Very high pressure
  
ANSWER: Very low pressure
7)   Dead weight gauge is used for the measurement of pressure of

a. About 1000 bar
b. About 2000 bar
c. About 5000 bar
d. About 7000 bar
  
ANSWER: About 7000 bar
8)   Bourdon tube is used for the measurement of gauge pressure of

a. Gas
b. Liquid fluid
c. Solid
d. Only (a) and (b)
e. All the above
  
ANSWER: Only (a) and (b)
9)   The resistances of potential transformer winding is minimized by using

a. Thick conductors and small length of turns
b. Thin conductors and small length of turns
c. Thin conductors and large length of turns
d. Thick conductors and large length of turns
  
ANSWER: Thick conductors and small length of turns
10)   The nominal ratio for a current transformer is given by

a. (rated primary winding current)/(rated secondary winding current)
b. (number of turns in the primary winding)/(number of turns in the secondary winding )
c. (number of turns in the secondary winding)/(number of turns in the primary winding )
d. (rated secondary winding current)/(rated primary winding current)
  
ANSWER: (rated primary winding current)/(rated secondary winding current)
11)   Moving iron power factor meter are suitable for 3 phase balanced circuits. It consists of

a. One control spring
b. Two control spring
c. Three control spring
d. No control spring
  
ANSWER: No control spring
12)   If the frequency of electrodynamic power factor meter is doubled then its reading will become

a. Twice of the original reading
b. Half of the original reading
c. Four times of the original reading
d. Remains unaffected
  
ANSWER: Remains unaffected
13)   A moving iron frequency meter consists of

a. Two inductive circuits connected in parallel
b. One inductive and one non inductive circuit connected in parallel
c. Two non inductive circuits connected in parallel
d. One inductive and one non inductive circuit connected in series
  
ANSWER: One inductive and one non inductive circuit connected in parallel
14)   The electrodynamic frequency meters have

a. Linear scale and their readings does not depends on voltage
b. Linear scale and their readings depends on voltage
c. Non linear scale and their readings does not depends on voltage
d. Non linear scale and their readings depends on voltage
  
ANSWER: Linear scale and their readings does not depends on voltage
15)   The earth resistance can be measured by 

a. Fall of potential method
b. Using an earth tester
c. Ducter ohmmeter method
d. Only (a) and (b)
e. All the above
  
ANSWER: Only (a) and (b)
16)   Electrical equipments are
generally earthed through an electrode to avoid shocks when someone
touches the body of the equipment. The earth resistance is effected by


a. Depth of electrodes buried in the soil
b. Shape and material of earth electrodes
c. Specific resistance of the soil surrounding the electrode
d. All of these
e. None of these
  
ANSWER: All of these
17)   When a voltmeter – ammeter
method is applied for the measurement of resistance, the voltmeter reads
a value of 8.28 V and the ammeter reading is 4.14 mA. Then the value of
the resistance will be


a. 2 kΩ
b. 2.0 kΩ
c. 2.00 kΩ
d. 2.000 kΩ
  
ANSWER: 2.00 kΩ
18)   At 2 MHz, the resonance is
obtained with a resonating capacitance value of 12 pF and at 400 kHz,
the resonance is obtained with resonating capacitance value of 320 pF.
Then the self capacitance of the coil is


a. 0.62 pF
b. 0.83 pF
c. 1.2 pF
d. 1.5 pF
  
ANSWER: 0.62 pF
19)   In AC bridges, the Wagner earth devices are used to

a. Remove all the earth capacitances from the bridge circuit
b. Remove harmonics
c. Reduce error caused by stray electric field
d. All of these
  
ANSWER: All of these
20)   Shielding of the capacitor is done to

a. Make the value of capacitor definite
b. Balance the bridge without any problem
c. Both (a) and (b)
d. None of these
  
ANSWER: Both (a) and (b)
21)   The indicating instruments with linear scale is

a. PMMC
b. Electrostatic instrument
c. Dynamometer instrument
d. Thermocouple instrument
  
ANSWER: PMMC
22)   The resistance potential divider method and capacitance potential divider method is used for

a. Both AC and DC
b. Former method can be used for both AC and DC and the later method can be used only for AC
c. Former method can be used for AC only and the later method can be used for both AC and DC
d. Former method can be used for DC only and the later method can be used only for AC
  
ANSWER: Former method can be used for both AC and DC and the later method can be used only for AC
23)   The range of electrostatic voltmeter can be extended by using 

a. Resistance potential divider method
b. Capacitance potential divider method
c. Both (a) and (b)
d. None of these
  
ANSWER: Both (a) and (b)
24)   The multiplying factor of electrostatic voltmeters is given by

a. ( C + C v ) / C
b. ( C + C v ) / C v
c. C / ( C + C v )
d. C v / ( C + C v )
  
ANSWER: ( C + C v ) / C
25)   In electrostatic instruments iron is not used for construction. These instruments are

a. Free from hysteresis and eddy current losses
b. Free from temperature errors
c. Dependent on temperature errors
d. Both (a) and (b)
e. None of the above
  
ANSWER: Both (a) and (b)
26)   If an electrostatic voltmeter is used on AC circuit and has non uniform waves, then it will read

a. Average values
b. RMS values
c. Peak values
d. All of these
  
ANSWER: RMS values
27)   Electrostatic voltmeter instruments are suitable for 

a. AC work only
b. DC work only
c. Both AC and DC work
d. None of these
  
ANSWER: Both AC and DC work
28)   A Kelvin’s multicellular voltmeter has a torsion head and a coach spring for

a. Protection against accidental fraction of suspension due to vibration
b. For zero adjustment
c. Torsion head for zero adjustment and coach spring for Protection against accidental fraction of suspension due to vibration
d. Torsion head for Protection against accidental fraction of suspension due to vibration and coach spring for zero adjustment
  
ANSWER: Torsion head for zero
adjustment and coach spring for Protection against accidental fraction
of suspension due to vibration
29)   In electrostatic voltmeters,
the principle of their operation is the force of attraction between
electric charges on neighboring plates between which potential
difference is maintained. The attracted – disc type electrostatic
instruments are used for the measurement of 


a. Very low voltages
b. Low voltages
c. High voltages
d. Very high voltages
  
ANSWER: Very high voltages
30)   Electrostatic instruments are generally used as 

a. Voltmeters
b. Ammeters
c. Wattmeters
d. Watt-hour meters
  
ANSWER: Voltmeters
31)   Due to overdamping, the instrument will become

a. Slow
b. Lethargic
c. Fast
d. Both (a) and (b)
  
ANSWER: Both (a) and (b)
32)   If the degree of damping of
an instrument should be adjusted to a value which is sufficient to
enable the pointer to rise quickly to its deflected position without
overshooting is called as


a. Overdamped
b. Dead beat
c. Underdamped
d. None of these
  
ANSWER: Dead beat
33)   In a Wheatstone bridge, the formula for finding unknown resistance (R2) is given by
R2 = ( R2 R3 ) / R1
Where, R1 = 150Ω ± 0.1%
R2 = 250Ω ± 0.1%
R3 = 300Ω ± 0.1%


a. R2 = 250Ω ± 0.1%
b. R2 = 300Ω ± 0.3%
c. R2 = 750Ω ± 0.3%
d. R2 = 500Ω ± 0.3%
  
ANSWER: R2 = 500Ω ± 0.3%
34)   While measuring resistance
by the voltmeter – ammeter method, the maximum possible percentage error
in the voltmeter and ammeter are ± 1.8% and ± 1.2% respectively. Then
the maximum possible percentage error in the value of resistance will be


a. ± 3%
b. ± 4%
c. ± 4.2%
d. ± 4.8%
  
ANSWER: ± 3%
35)   If the resistance in a
circuit is given by 80 Ω ± 0.2% and the current flowing through it is 5A
± 0.1%, then the uncertainty in the power will be


a. ± 0.2 %
b. ± 0.4 %
c. ± 0.6 %
d. ± 0.8 %
  
ANSWER: ± 0.4 %
36)   If the two voltage
measurements are V1 = 150 ± 2% and V2 = 100 ± 4% respectively. Then the
maximum percentage error in the sum of two voltage measurements is


a. ± 2.4 %
b. ± 2.6 %
c. ± 2.8 %
d. ± 3.4 %
  
ANSWER: ± 2.8 %
37)   When a 100 V moving iron
voltmeter is of accuracy class 1 – 0 is used in a circuit, it reads 50
V. Then the maximum possible percentage error in the reading is


a. 1 %
b. 2 %
c. 2.5 %
d. 3 %
  
ANSWER: 2 %
38)   In a measurement system,

a. A single measurement components may have both random errors and systematic errors
b. A measurement system consists of several components with each component having separate errors
c. Both the statement (a) & (b) are true
d. Neither statement (a) nor statement (b) is true
  
ANSWER: Both the statement (a) & (b) are true
39)   The error between mean of finite data set and mean of infinite data set is known as 

a. True error of the mean
b. Standard error of the mean
c. Finite error
d. Infinite error
  
ANSWER: Standard error of the mean
40)   If the quantity to be
measured remains constant during the process of taking the repeated
measurements then the random errors can be eliminated by


a. Calculating the mean of the number of repeated measurements
b. Calculating the median of the number of repeated measurements
c. Calculating the sum of the numbers of repeated measurements
d. Either (a) or (b)
  
ANSWER: Either (a) or (b)
41)   In liquid crystal displays, the liquid crystal exhibits properties of

a. Liquid
b. Solids
c. Gases
d. Both (a) and (b)
  
ANSWER: Both (a) and (b)
42)   In light emitting diode, the available light emitting region is 

a. Less than 2.5 mm
b. From 2.5 to 25 mm
c. Greater than 25 mm
d. Greater than 50 mm
  
ANSWER: From 2.5 to 25 mm
43)   Resolver works on the principal of mutual inductance variation. It is mainly used for the measurement of

a. Linear displacement
b. Non – linear displacement
c. Rotary motion
d. All of these
  
ANSWER: Rotary motion
44)   In rotary variable differential transformer, the mutual inductance between the primary and secondary coils varies

a. Linearly with the angular displacement
b. Non – linearly with the angular displacement
c. Linearly with the linear displacement
d. Non – linearly with the linear displacement
  
ANSWER: Linearly with the angular displacement
45)   LVDT which is an instrument for the measurement of displacement, works on the principal of 

a. Linear inductance
b. Non – linear inductance
c. Mutual inductance
d. Linear capacitance
  
ANSWER: Mutual inductance
46)   The instruments used for the measurement of pressure is / are

a. Bellows
b. Diaphragms
c. Fiber optic pressure sensors
d. All of these
e. None of the above
  
ANSWER: All of these
47)   A capacitive pressure sensor has a typical measurement uncertainty of

a. ± 0.2%
b. ± 0.4%
c. ± 0.1%
d. ± 0.8%
  
ANSWER: ± 0.2%
48)   If the displacement is measured with strain gauge then the number of strain gauge normally required are

a. One
b. Two
c. Three
d. Four
  
ANSWER: Four
49)   If an instrument transformer is used to extend the ranges of AC instrument, then its reading will depend on

a. R
b. L
c. C
d. All of these
e. None of these
  
ANSWER: None of these
50)   The potential transformers are used to measure large voltage using

a. High range voltmeter
b. Low range voltmeter
c. High range ammeter
d. Low range ammeter
  
ANSWER: Low range voltmeter
51)   The meter of a vibrating reed frequency meter depends for its indications on the

a. Electrical resonance of thin flat steel reeds
b. Mechanical resonance of thin flat steel reeds
c. Mechanical resonance of thick flat steel reeds
d. Electrical resonance of thick flat steel reeds
  
ANSWER: Mechanical resonance of thin flat steel reeds
52)   Vibration galvanometer are generally used 

a. For measuring electric charges
b. As null – point detectors in ac bridges
c. As null – point detectors in dc bridges
d. For measuring power
  
ANSWER: As null – point detectors in ac bridges
53)   Ballistic galvanometer are principally used for the measurement of 

a. Current
b. Voltage
c. Power
d. Electric charges
  
ANSWER: Electric charges
54)   The two wattmeters used for
the measurement of power input read 50 kW each. What will be the
readings of the two wattmeters if the power factor is changed to 0.8
leading keeping the total input power same?


a. 28.35W, 71.65W
b. 31.25W, 73.71W
c. 33.33W, 73.33W
d. 38.35W, 75.5W
  
ANSWER: 28.35W, 71.65W
55)   If a capacitor is connected
across a portion of resistance of multiplier of the wattmeter then the
pressure coil of the circuit becomes


a. Inductive
b. Non inductive
c. Capacitive
d. Non capacitive
  
ANSWER: Non inductive
56)   For the measurement of unknown inductance in terms of known capacitance, the suitable ac bridges are

a. Maxwell and Schering bridge
b. Maxwell and Wien’s bridge
c. Maxwell and Hay’s bridge
d. Hay’s and Wien’s bridge
  
ANSWER: Maxwell and Hay’s bridge
57)   The Wien’s bridges is suitable for the measurement of frequency of the range of

a. Less than 100 Hz
b. 100 Hz to 100 kHz
c. 1 kHz to 100 MHz
d. More than 100 MHz
  
ANSWER: 100 Hz to 100 kHz
58)   In a slide wire
potentiometer, for a voltage source of 1.012 V the jockey is kept at
101.2 cm. If the potentiometer has 20 wires of 1 m each and the
resistance of wires is 800 ohm, then the value of the working current is


a. 15 mA
b. 20 mA
c. 25 mA
d. 27 mA
  
ANSWER: 25 mA
59)   For the measurement of low
resistances from few ohms down to one micro ohm, which of the following
instrument is not suitable?


a. Potentiometer method
b. Ammeter – voltmeter method
c. Ohmmeter
d. Kelvin double bridge method
  
ANSWER: Ohmmeter
60)   For the measurement of low resistances, Kelvin’s double bridge has high accuracy because

a. It has two set of ratio arms which eliminates effect of resistance of connecting lead
b. It has a null indicating galvanometer
c. It has two null indicator
d. It has four sets of ratio arms which eliminates the effect of resistance of connecting lead
  
ANSWER: It has two set of ratio arms which eliminates effect of resistance of connecting lead
61)   Swamping resistance is a resistance made up of 

a. Alloy of manganin and copper
b. Alloy of aluminium and copper
c. Alloy of nickel and cobalt
d. Alloy of manganin and aluminium
  
ANSWER: Alloy of manganin and copper
62)   In a moving coil of a meter swamping resistance is added to 

a. Reduce the frequency error
b. Reduce the temperature error
c. Reduce the power consumption
d. All of these
  
ANSWER: Reduce the temperature error
63)   Which among the following is not true about the induction instruments?

a. It can be used for ac measurements only
b. Damping is very efficient in case of induction instruments
c. Compensation for frequency temperature is not required
d. Cost is relatively high
  
ANSWER: Compensation for frequency temperature is not required
64)   The temperature errors in induction instruments can be compensated by 

a. Hunting in both ammeters and voltmeters
b. Combination of shunt and swamping resistance in both ammeters and voltmeters
c. Hunting in case of ammeters and Combination of shunt and swamping resistance in case of voltmeters
d. Combination of shunt and swamping resistance in case of ammeters and hunting in case of voltmeters
  
ANSWER: Hunting in case of ammeters and Combination of shunt and swamping resistance in case of voltmeters
65)   The frequency errors in induction instruments can be compensated by the use of

a. Non inductive shunt in both ammeters and voltmeters
b. Non inductive shunt in case of ammeters and are generally self compensated in case of voltmeters
c. Self compensated in case of both ammeters and voltmeters
d. Self compensated in case of ammeters and non inductive shunt in case of voltmeters
  
ANSWER: Non inductive shunt in case of ammeters and are generally self compensated in case of voltmeters
66)   For reducing the errors in an induction instrument the alternating current to be measured has

a. Same frequency with which the instrument was calibrated
b. High frequency compared with which the instrument was calibrated
c. Low frequency compared with which the instrument was calibrated
d. None of these
  
ANSWER: Same frequency with which the instrument was calibrated
67)   In induction voltmeter, split phase windings are obtained by connecting a

a. High resistances in series with windings of both the magnets
b. High resistance in series with the winding of one magnet and an inductive coil in series with the windings of other magnet
c. An inductive coil in series with the winding of one magnet and a capacitance in series with the windings of other magnet
d. Inductive coils in series with the winding of both the magnets
  
ANSWER: High resistance in
series with the winding of one magnet and an inductive coil in series
with the windings of other magnet
68)   A cylindrical type with split phase winding induction ammeters employs

a. A rotating disc
b. A hollow aluminium drum
c. A single flux producing winding
d. Either (a) or (b)
  
ANSWER: A hollow aluminium drum
69)   Induction type instruments are generally used as

a. Ammeter
b. Voltmeter
c. Wattmeter
d. All of these
e. None of these
 
ANSWER: All of these
70)   Damping torque is the torque which acts on

a. Stationary system of the instrument
b. Moving system of the instrument only when it is stationary
c. Moving system of the instrument only when it is moving
d. Stationary system of the instrument only when the moving system is moving
  
ANSWER: Moving system of the instrument only when it is moving
71)   A
deflection of 90 degree is produced when a current of 10 A flows
through the circuit and the torque of the ammeter vary as the square of
the current through it. If a current of 8 A flows through it, then the
deflection obtained when the instrument is spring controlled and when
the instrument is gravity controlled are


a. 39.79 degree, 57.6 degree
b. 47.55 degree, 35.67 degree
c. 57.6 degree, 39.79 degree
d. 35.67 degree, 47.55 degree
  
ANSWER: 57.6 degree, 39.79 degree
72)   The gravity controlled instruments has to be kept 

a. Vertical
b. Horizontal
c. Inclined at 45 degree
d. Inclined at 75 degree
  
ANSWER: Vertical
73)   Random errors in a measurement system are due to

a. Environmental changes
b. Use of uncalibrated instrument
c. Poor cabling practices
d. Unpredictable effects
  
ANSWER: Unpredictable effects
74)   Calibration of instrument is
an important consideration in measurement system. The errors due to
instruments being out of calibration can be rectified by


a. Increasing the frequency of recalibration
b. Increasing the temperature coefficient
c. Increasing the susceptibility of measuring instrument
d. Decreasing the frequency of recalibration
  
ANSWER: Increasing the frequency of recalibration
75)   The undesirable characteristics of a measuring system is / are

a. Drift
b. Dead zone
c. Non linearity
d. All of these
  
ANSWER: All of these
76)   If the instrument is used in wrong manner while application, then it will results in

a. Systematic error
b. Instrument error
c. Random error
d. Environmental error
  
ANSWER: Instrument error
77)   Suitable method for the reduction of systematic errors is / are

a. Instrument must be designed carefully
b. By introducing an equal and
opposite environmental input for compensating the effect of
environmental input in a measurement system
c. By adding high gain feedback to measurement system
d. All of these
  
ANSWER: All of these
78)   The systematic errors of an instrument can be reduced by making

a. The sensitivity of instrument to environmental input as low as possible
b. The sensitivity of instrument to environmental input as high as possible
c. Systematic errors does not depend on the sensitivity of instrument
d. None of these
  
ANSWER: The sensitivity of instrument to environmental input as low as possible
79)   The magnitude of environment – induced variation from the specified calibration condition is quantified by

a. Sensitivity drift
b. Zero drift
c. Backlash
d. Both (a) & (b)
  
ANSWER: Both (a) & (b)
80)   In a moving coil voltmeter, the input resistance of the meter can be increased by 

a. Increasing the number of turns in the coil
b. Decreasing the number of turns in the coil
c. Using the same number of coil turns made up of high resistance material
d. Both (a) & (c)
  
ANSWER: Both (a) & (c)
81)   Depending on whether the display is a numeric or alphanumeric, the segmental display is

a. 7 segmental
b. 14 segmental
c. 21 segmental
d. Either (a) or (b)
e. None of the above
  
ANSWER: Either (a) or (b)
82)   The measurements which can be simplified by using X – Y recorders is / are

a. Speed – torque characteristics of motors
b. Regulation curves of power supplies
c. Hysteresis curves
d. All of these
  
ANSWER: All of these
83)   Potentiometer is used for the measurement of 

a. Linear displacement
b. Angular displacement
c. Non – linear displacement
d. Only (1) and (2)
e. All the above
  
ANSWER: Only (1) and (2)
84)   The displacement measuring instruments is / are

a. Potentiometer
b. LVDT
c. RVDT
d. All of these
  
ANSWER: All of these
85)   In fibre – optic level sensors, the amount of light loss depends on 

a. The proportion of cable that is submerged in the liquid
b. Amount of light which is reflected back
c. The proportion of cable that is not in the liquid
d. Amount of light which is not reflected back
  
ANSWER: The proportion of cable that is submerged in the liquid
86)   Instrument which is capable of discriminating temperature differences of even 0.1 degree Celsius is

a. Fibre – optic level sensors
b. Laser method
c. Thermography
d. Vibrating level sensors
  
ANSWER: Thermography
87)   Contact devices used for the measurement of level are

a. Less reliable then devices which does not make contact with the material
b. More reliable then devices which does not make contact with the material
c. Less reliable then devices which makes contact with the material
d. More reliable then devices which makes contact with the material
  
ANSWER: Less reliable then devices which does not make contact with the material
88)   With the increase in the intensity of light, the resistance of a photovoltaic cell

a. Increases
b. Decreases
c. Remains same
d. None of these
  
ANSWER: Decreases
89)   For the measurement of pressure the instruments used can be

a. Mechanical
b. Electro – mechanical
c. Electronic
d. All of these
e. None of these
  
ANSWER: All of these
90)   If at one end, the two wires
made of different metals are joined together then a voltage will get
produced between the two wires due to difference of temp between the two
ends of wires. This effect is observed in


a. Thermocouples
b. Thermistors
c. RTD
d. Ultrasonics
  
ANSWER: Thermocouples
91)   Primary current in a current transformer is determined by

a. The load on the system
b. The load on its own secondary
c. The load on its own primary
d. All of these
  
ANSWER: The load on the system
92)   The transformer ratio of the transformer depends upon the 

a. Exciting current
b. Secondary current
c. Power factor of secondary circuit
d. All of these
  
ANSWER: All of these
93)   During load test on 3 phase
induction motor, the readings of the two wattmeters are -5.5 kW and
+12.5 kW respectively. If the line voltage is 420 V then the line
current will be


a. 38.91 A
b. 41.02 A
c. 42.10 A
d. 43.94 A
  
ANSWER: 43.94 A
94)   If the reading of the two
wattmeters is equal and opposite while measuring power in a 3 phase
induction motor then the power factor of the load will be


a. Unity
b. Zero
c. 0.5 lagging
d. 0.5 leading
  
ANSWER: Zero
95)   The full scale current of a
galvanometer with internal resistance of 800 ohm is 8 A. what will be
the multiplying power of 80 ohm shunt with this galvanometer?


a. 8
b. 9
c. 10
d. 11
  
ANSWER: 11
96)   In L – C connected wattmeter, compensated coil is used. The error in the wattmeter is due to power consumed by the

a. Current coil
b. Potential coil
c. Inductor
d. Capacitor
  
ANSWER: Potential coil
97)   The AC Bridge which is used for the measurement of frequency is

a. Schering bridge
b. Wien bridge
c. Hay’s bridge
d. Anderson bridge
  
ANSWER: Wien bridge
98)   Schering bridges are used for the measurement of 

a. Unknown capacitance
b. Dielectric loss
c. Power factor
d. All of these
e. None of these
  
ANSWER: All of these
99)   The bridge suitable for the measurement of capacitance is / are

a. Anderson’s bridge
b. Hay’s bridge
c. Owen’s bridge
d. None of these
  
ANSWER: None of these
100)   The method / methods suitable for the measurement of low resistance is / are

a. Ammeter – voltmeter method
b. Kelvin’s double bridge method
c. Potentiometer method
d. All of these
  
ANSWER: All of these
101)   A
highly sensitive galvanometer is used in Wheatstone bridge and it can
detect a current as low as 80 pA. The resistances of each arm of bridge
are 800 ohm and the resistance of galvanometer is 40 ohm. If an input of
20 V is applied to the bridge then the smallest change in resistance
which can be detected is


a. 10.752 μA
b. 15.280 μA
c. 17.351 μA
d. 23.719 μA
  
ANSWER: 10.752 μA
102)   In a Wheatstone bridge, if P = 10 ± 1%, Q = 100 ± 1%, R = 20 ± 1% and S is unknown then the unknown resistance will be

a. 200 ± 1%
b. 200 ± 2%
c. 200 ± 3%
d. 100 ± 1%
  
ANSWER: 200 ± 3%
103)   The heater wire of thermocouple instruments are made of smaller area of cross section to 

a. reduce the skin effect
b. reduce temperature error
c. reduce frequency error
d. increase inductance
  
ANSWER: reduce the skin effect
104)   The thermocouple ammeter scale is 

a. Linear
b. Cramped at low end and open at high end
c. Open at low end and cramped at high end
d. Cramped at the middle
  
ANSWER: Cramped at low end and open at high end
105)   The thermocouple instruments works on the principle of Seebeck effect. The amount of heat produced is

a. Directly proportional to the current
b. Directly proportional to the square of current
c. Inversely proportional to the current
d. Inversely proportional to the square of current
  
ANSWER: Directly proportional to the square of current
106)   In a portable instrument,
the effect of stray magnetic field on actuating torque will be maximum
when the operating field and stray fields are


a. Parallel to each other
b. Perpendicular to each other
c. Inclined at 45 degree
d. Opposite to each other
  
ANSWER: Parallel to each other
107)   Megger is a portable instrument. It is used for the measurement of

a. Low inductance
b. Low resistance
c. High inductance
d. High resistance
  
ANSWER: High resistance
108)   In the given frequency range, which type of instrument will have highest accuracy

a. electrodynamometer
b. hot – wire instrument
c. electrostatic instrument
d. PMMC
  
ANSWER: electrodynamometer
109)   Power consumption in permanent magnet moving coil instrument and hot – wire instruments are

a. Low, low
b. Low, high
c. High, low
d. High, high
  
ANSWER: Low, high
110)   The current sensitive instruments are

a. PMMC
b. Hot wire instruments
c. Electrostatic instruments
d. Both (a) and (b)
  
ANSWER: Both (a) and (b)
111)   The scales of gravity controlled instruments are

a. Uniform
b. Non – uniform and cramped or crowded at the middle
c. Non – uniform and cramped or crowded at their lower ends
d. Non – uniform and cramped or crowded in the first half
  
ANSWER: Non – uniform and cramped or crowded at their lower ends
112)   In a gravity controlled type indicating instrument, the current flowing through the circuit is

a. Directly proportional to the cosine of angle of deflection
b. Directly proportional to the sine of angle of deflection
c. Directly proportional to the tan of the angle of deflection
d. Directly proportional to the angle of deflection
  
ANSWER: Directly proportional to the sine of angle of deflection
113)   If the impedance of the
instrument measuring the output voltage of the bridge circuit is less
than the component resistance then


a. The instrument will load the bridge circuit
b. The instrument will draw current from the circuit
c. Supply current to the circuit
d. Both (a) & (b)
e. None of the above
  
ANSWER: Both (a) & (b)
114)   In bridge circuit, the impedance of the instrument measuring the output voltage must be

a. Equal to the component resistance of the circuit
b. Very large compared to the component resistance of the circuit
c. Very small compared to the component resistance
d. Less than compared to the component resistance but not very small
  
ANSWER: Very large compared to the component resistance of the circuit
115)   Systematic errors in a measurement system are caused by 

a. System disturbance during measurement
b. Effect of environmental changes
c. Use of uncalibrated instruments
d. All of these
  
ANSWER: All of these
116)   In the systematic errors, the errors in the output of the measurement system are

a. All the errors will be positive
b. All the errors will be negative
c. Either all the errors will be positive or all the errors will be negative
d. None of the these
 
ANSWER: Either all the errors will be positive or all the errors will be negative
117)   The difference between the measured value and the true value is known as

a. Relative error
b. Random error
c. Absolute error
d. Systematic error
 
ANSWER: Absolute error
118)   The process of measurement 

a. Always disturbs the system being measured
b. It may or may not disturb the system being measured
c. Never disturbs the system being measured
d. None of these
  
ANSWER: Always disturbs the system being measured
119)   Commercial accelerometer,
which is a second order instruments are generally designed for the
damping ratio of the range of


a. 0.2 – 0.4
b. 0.6 – 0.8
c. 0.707 – 1
d. 1 – 1.5
  
ANSWER: 0.6 – 0.8

120)   For a second order instrument if the value of the damping ratio is equal to zero, then the

a. Output will exhibit constant amplitude oscillation
b. Initially output will be oscillatory and gradually it will die down
c. Initially output will be oscillatory and gradually amplitude of oscillation will increase
d. Output does not exhibit any oscillations
  
ANSWER: Output will exhibit constant amplitude oscillation
121)   X – Y recorder is the type of

a. Graphic recorders
b. Oscillographic recorders
c. Magnetic tape recorders
d. Digital recorders
  
ANSWER: Graphic recorders
122)   The different types of analog recorders are

a. Graphic recorders
b. Oscillographic recorders
c. Magnetic tape recorders
d. All of these
  
ANSWER: All of these
123)   A vibrating level sensors consist of 

a. One piezoelectric oscillators
b. Two piezoelectric oscillators
c. Three piezoelectric oscillators
d. Four piezoelectric oscillators
  
ANSWER: Two piezoelectric oscillators
124)   In radiation methods, the detector system is located

a. At the top of the liquid filled tank
b. At the bottom of liquid filled tank
c. In middle of the liquid filled tank
d. Outside a liquid filled tank
  
ANSWER: Outside a liquid filled tank
125)   If the ambient temperature is doubled and pressure fluctuates, then the transmission time of radar through air is 

a. Almost unaffected and remains same
b. Increases
c. Decreases
d. None of these
  
ANSWER: Almost unaffected and remains same
126)   The transducer used for the measurements is / are

a. Resistance temperature detectors
b. Thermistors
c. Ultrasonic
d. All of these
  
ANSWER: All of these
127)   The linear variable differential transformer transducer is

a. Inductive transducer
b. Non – inductive transducer
c. Capacitive transducer
d. Resistive transducer
 
ANSWER: Inductive transducer
128)   Constantan is used for measurement of dynamic strains. It is an alloy of

a. Constantan is used for measurement of dynamic strains. It is an alloy of
b. Nickel and molybdenum
c. Nickel and chromium
d. Copper and nickel
  
ANSWER: Copper and nickel
129)   Strain gauge is a 

a. Active device and converts mechanical displacement into a change of resistance
b. Passive device and converts electrical displacement into a change of resistance
c. Passive device and converts mechanical displacement into a change of resistance
d. Active device and converts electrical displacement into a change of resistance
  
ANSWER: Passive device and converts mechanical displacement into a change of resistance
130)   Thermistor is a transducer. Its temperature coefficient is

a. Negative
b. Positive
c. Zero
d. None of these
  
ANSWER: Negative
131)   For the measurement of energy and power it is essential to know 

a. Only the transformation ratio
b. Phase angle between the primary and secondary currents
c. Both (a) and (b)
d. None of these
  
ANSWER: Both (a) and (b)
132)   Current transformers and potential transformers are used to increase the ranges of

a. AC ammeter and AC voltmeter respectively
b. AC ammeter and DC voltmeter respectively
c. DC ammeter and DC voltmeter respectively
d. DC ammeter and AC voltmeter respectively
  
ANSWER: AC ammeter and AC voltmeter respectively
133)   If the reading of one
wattmeter is four times the other wattmeter while measuring the input
power of 3 phase induction motor then the power factor of the load will
be


a. 0.56
b. 0.69
c. 0.74
d. 0.81
 
ANSWER: 0.69
134)   What will be the power
factor of an inductive load if the reading of the two wattmeters
connected to measure input power of a 3 phase induction motor is 6: 3?


a. 0.86
b. 0.89
c. 0.91
d. 0.95
  
ANSWER: 0.86
135)   The readings of the two
wattmeter used for the measurement of power input to a 3 phase induction
motor are 850 W and 250 W respectively. The power factor of the motor
is


a. 0.73
b. 0.76
c. 0.79
d. 0.85
  
ANSWER: 0.73
136)   A wattmeter has a pressure
coil resistance of 5K ohm and current coil resistance of 0.02 ohm. What
load will give equal error with the two connections if the load current
is 15 A at a voltage of 240 V and 0.8 power factor.


a. 20 A
b. 24 A
c. 28 A
d. 32 A
  
ANSWER: 24 A
137)   The Schering bridges can be used at

a. low voltage
b. high voltage
c. medium voltage
d. both (a) and (b)
e. all the above
  
ANSWER: both (a) and (b)
138)   If δ is the loss angle then the dissipation factor is given by 

a. sin δ
b. cos δ
c. tan δ
d. cot δ
 
ANSWER: tan δ
139)   The dielectric loss of pure capacitor is equal to

a. 1
b. 0
c. Maximum
d. None of these
  
ANSWER: 0
140)   To produce a change of 2 mm
in deflection of galvanometer, a change of 4 ohm is required in the
unknown arm of a Wheatstone bridge. The sensitivity of the galvanometer
is


a. 1 mm / ohm
b. 0.5 mm / ohm
c. 1.5 mm / ohm
d. 2 mm / ohm
  
ANSWER: 0.5 mm / ohm
141)   The
resistances of the various arms of Wheatstone bridge are P = 500 ohm, Q
= 50 ohm, R = 1010 ohm and S = 100 ohm. The emf of the batter is 5 V
and the current sensitivity of galvanometer is 8 mm / μ A. If the
internal resistance of the galvanometer is 80 ohm then the deflection of
galvanometer and the sensitivity of the bridge in terms of deflection
per unit change of resistance are


a. 151.2 mm, 30.24 mm / ohm
b. 100 mm, 21.03 mm / ohm
c. 186 mm, 40.37 mm / ohm
d. 193 mm, 20.74 mm / ohm
  
ANSWER: 151.2 mm, 30.24 mm / ohm
142)   Wheatstone bridge is suitable for the measurement of

a. Low resistance
b. Medium resistance
c. High resistance
d. Very high resistance
  
ANSWER: Medium resistance
143)   Hot – wire instruments are suitable for

a. AC work only
b. DC work only
c. Both AC and DC work
d. None of these
  
ANSWER: Both AC and DC work
144)   The deflection angle in hot wire instruments is

a. Directly proportional to the current
b. Directly proportional to the square of current
c. Inversely proportional to the current
d. Inversely proportional to the square of current
  
ANSWER: Directly proportional to the square of current
145)   For a dynamometer
wattmeter, the variation of inductance with angular position of moving
system is 0.06 mH/radian and spring constant is 10 X 10-6 N
-m / radian. The current flowing in the instrument is 8 A. If the full
scale deflection is 76 degree, then the current required in the voltage
coil at full scale in d.c. circuit is


a. 27.6 μA
b. 29.89 μA
c. 35.3 μA
d. 37.28 μA
  
ANSWER: 27.6 μA
146)   A electrodynamic ammeter has current flowing through it of 20 A and torsional constant of controlling spring of 10-6 N
– m / degree. If the mutual inductance changes uniformly at the rate of
0.0025 μ H / degree, then its angular deflection for full scale is 


a. 43.68 degree
b. 57.29 degree
c. 68.32 degree
d. 69.69 degree
  
ANSWER: 57.29 degree
147)   In an electrodynamic instrument, the number of control springs present is / are

a. Two
b. One
c. Four
d. Zero
  
ANSWER: Two
148)   The scale of electrodynamic instrument when it is used as ammeter and when it is used as voltmeter is

a. Uniform, uniform
b. Crowded near zero, crowded near zero
c. Cramped near zero, cramped in the middle
d. Uniform, cramped near zero
  
ANSWER: Crowded near zero, crowded near zero
149)   The equivalent inductance of fixed coil and moving coil of electrodynamic instrument is given by

a. L1 + L2 + 2M
b. L1 + L2 – 2M
c. L1 + L2 + M
d. L1 + L2 – M
  
ANSWER: L1 + L2 + 2M
150)   Electrodynamic instruments can be used as

a. Ammeter
b. Voltmeter
c. Wattmeter
d. All of these
  
ANSWER: All of these
151)   In measuring instruments, spiral springs are provided to

a. Lead current
b. Produce controlling torque
c. Produce damping torque
d. Lead current and produce controlling torque
  
ANSWER: Lead current and produce controlling torque
152)   In a spring controlled type indicating instruments, if the controlling torque is equal to the deflecting torque then

a. Angle of deflection will be maximum
b. Current flowing through it will be maximum
c. Angle of deflection will be zero
d. Angle of deflection will be directly proportional to the current flowing through it
  
ANSWER: Angle of deflection will be directly proportional to the current flowing through it
153)   If a balloon is equipped
with temperature and altitude measuring instruments, then the order of
the temperature measuring and altitude measuring instruments are


a. Zero order, first order
b. Both are first order instruments
c. Both are zero order instruments
d. First order, zero order
  
ANSWER: First order, zero order
154)   A zero order system is the
one in which output changes instantaneously as the input changes. The
example of zero order system is


a. Potentiometer
b. Liquid – in – glass thermometer
c. Accelerometer
d. Transducer
  
ANSWER: Potentiometer
155)   Backlash is commonly
experienced in gear sets used to convert between translational and
rotational motion. Backlash is a typical cause of 


a. Hysteresis
b. Dead space
c. Zero drift
d. Sensitivity drift
  
ANSWER: Dead space
156)   If an instruments exhibits hysteresis then

a. It also displays dead space
b. It will not display any dead space
c. Either (a) or (b)
d. None of these
  
ANSWER: It also displays dead space
157)   In a measuring instrument, dead space is defined as the 

a. Range of different input values over which there is no change in output values
b. Range of different output values for the same input values
c. Either (a) or (b)
d. None of these
  
ANSWER: Range of different input values over which there is no change in output values
158)   Hysteresis most commonly occurs in instruments that contains

a. Springs
b. Electrical windings formed round on iron core
c. Both (a) and (b)
d. None of these
  
ANSWER: Both (a) and (b)
159)   The non coincidence between loading and unloading curves is known as

a. Zero drift characteristics
b. Sensitivity drift characteristics
c. Hysteresis
d. Zero drift plus sensitivity drift characteristics
  
ANSWER: Hysteresis
160)   Can an instrument suffer both zero drift and sensitivity drift at the same time?

a. Yes
b. No
c. It depends on the supply voltage
d. None of these
  
ANSWER: Yes
161)   Q meter is used to measure the properties of

a. Inductive coils
b. Non inductive coils
c. Capacitive coils
d. Both (a) and (c)
  
ANSWER: Both (a) and (c)
162)   In the beginning, all the outputs of the successive approximation type register is at

a. Logic zero
b. Logic one
c. Toggling
d. None of these
  
ANSWER: Logic zero
163)   In ultrasonic level gauge, the ultrasonic source is placed at the

a. Bottom of the vessel containing the liquid
b. Top of the vessel containing the liquid
c. Middle of the vessel containing the liquid
d. Far from the vessel containing the liquid
  
ANSWER: Bottom of the vessel containing the liquid
164)   Capacitive devices are used for the level measurement of

a. Only liquid
b. Solid in powdered form
c. Both (a) and (b)
d. None of these
  
ANSWER: Both (a) and (b)
165)   The most common application of float system is

a. To monitor the fuel tank level in motor vehicle
b. To monitor the flow of solid
c. To monitor the flow of liquid
d. All of these
  
ANSWER: To monitor the fuel tank level in motor vehicle
Explanation: 
No explanation is available for this question!
166)   Potentiometric transducers are used for the measurement of

a. Pressure
b. Displacement
c. Humidity
d. Both (a) and (b)
  
ANSWER: Both (a) and (b)
167)   Function of transducer is to convert 

a. Electrical signal into non electrical quantity
b. Non electrical quantity into electrical signal
c. Electrical signal into mechanical quantity
d. All of these
  
ANSWER: Non electrical quantity into electrical signal
168)   The phase difference between two waveforms in the below figure is given by

q23.png
a. ∅ = sin -1 Y1 / Y2
b. ∅ = sin -1 Y2 / Y1
c. ∅ = tan -1 Y2 / Y1
d. ∅ = tan -1 Y1 / Y2
  
ANSWER: ∅ = sin -1 Y1 / Y2
169)   For friction compensation in an induction watt-hour meter is done by making 

a. The ratio of the shunt magnet flux and series magnet flux large with the help of two shading bands
b. The ratio of the series magnet flux and shunt magnet flux large with the help of two shading bands
c. The ratio of the shunt magnet flux and series magnet flux large with the help of three shading bands
d. The ratio of the series magnet flux and shunt magnet flux large with the help of three shading bands
  
ANSWER: The ratio of the shunt magnet flux and series magnet flux large with the help of two shading bands
170)   In induction watt – hour meter, due to shunt magnet the torque is not zero power factor. It can be compensated by using

a. Shading ring
b. Power factor compensator
c. Drilling holes in the disc on a diameter
d. Both (a) and (b)
  
ANSWER: Both (a) and (b)
171)   The scale of induction wattmeter extends over

a. 70 degree
b. 120 degree
c. 180 degree
d. 300 degree
  
ANSWER: 300 degree
172)   In induction type wattmeter both current and pressure coils are required. For obtaining the required phase difference 

a. Shaded pole principle is used
b. Two separate ac magnets are used
c. Only one ac magnets are used
d. All of these
  
ANSWER: Two separate ac magnets are used
173)   The frequency and supply voltage of induction wattmeters are

a. Constant, constant
b. Constant, variable
c. Variable, constant
d. Variable, variable
  
ANSWER: Constant, constant
174)   Induction wattmeters can be used with 

a. Only AC supply
b. Only DC supply
c. Both AC and DC supply
d. None of these
  
ANSWER: Only AC supply
175)   Anderson bridges is suitable for the measurement of

a. Resistance
b. Inductance
c. Capacitance
d. All of these
  
ANSWER: Inductance
176)   The Hay’s bridge is suitable for the measurement of inductances of coils with Q factor 

a. More than 10
b. Less than 1
c. More than 1
d. Less than 10
  
ANSWER: More than 10
177)   If C4 is the capacitance and R4 is the resistance of Hay’s bridge, then the Q factor of Hay’s bridge is given by

a. 1 / (ω C4 R4)
b. ω C4 R4
c. (ω C4) / R4
d. (ω R4) / C4
  
ANSWER: 1 / (ω C4 R4)
178)   During a test, the strain
gauge with resistance of 200 ohm undergoes a change of 0.120 ohm and the
strain of the gauge is 1.2 X 10 -4. Then the gauge factor will be


a. 4
b. 5
c. 4.5
d. 6
  
ANSWER: 5
179)   The sensitivity of the bridge is maximum when

a. P / R = Q / S = 0
b. P / R = 1
c. Both (a) and (b)
d. None of the above
  
ANSWER: P / R = 1
180)   The sensitivity of Wheatstone bridge is defined as ratio of

a. Deflection of the galvanometer to the unit fractional change in the value of unknown resistance
b. Square of the deflection of the galvanometer to the unit fractional change in the value of unknown resistance
c. Deflection of the galvanometer to the twice of the unit fractional change in the value of unknown resistance
d. Unit fractional change in the value of unknown resistance to the deflection of the galvanometer
  
ANSWER: Deflection of the galvanometer to the unit fractional change in the value of unknown resistance

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