MCQOPTIONS
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MCQOPTIONS
This section includes 503 Mcqs, each offering curated multiple-choice questions to sharpen your ENGINEERING SERVICES EXAMINATION (ESE) knowledge and support exam preparation. Choose a topic below to get started.
| 251. |
An amplifier has to amplify pulses of 1 H-s duration. The minimum bandwidth of amplifier must be |
| A. | 10 kHz |
| B. | 10 MHz |
| C. | 1 kHz |
| D. | 1 MHz |
| Answer» E. | |
| 252. |
A moving iron instrument has |
| A. | two iron vanes, one fixed and one movable |
| B. | two movable iron vanes |
| C. | two aluminium vanes, one fixed and one movable |
| D. | two vanes, one fixed made of Aluminium and the other movable made of iron |
| Answer» B. two movable iron vanes | |
| 253. |
Assertion (A): Thermocouple instruments can be used for ac only. Reason (R): Thermocouple instrument has a non linear scale. |
| A. | Both A and R are true and R is correct explanation of A |
| B. | Both A and R are true but R is not correct explanation of A |
| C. | A is true R is false |
| D. | A is false R is true |
| Answer» E. | |
| 254. |
The dimensions of permittivity are |
| A. | L¯³M¯¹T²Q² |
| B. | L¯¹M¯¹T²Q² |
| C. | L²MT¯¹Q¯¹ |
| D. | L¯²M¯¹T²Q² |
| Answer» B. L¯¹M¯¹T²Q² | |
| 255. |
In Schering bridge, the potential of detector above earth potential is about |
| A. | a few volts |
| B. | 10 kV |
| C. | 1000 V |
| D. | either (a) or (b) |
| Answer» B. 10 kV | |
| 256. |
Acoustic strain gauges |
| A. | have good linearity of measurement |
| B. | do not have long term stability |
| C. | have a large range of measurement |
| D. | have an accuracy range of 0.1-1% depending on environment |
| Answer» E. | |
| 257. |
Which instrument is based on induction principle? |
| A. | Dynamometer wattmeter |
| B. | Induction wattmeter |
| C. | Energy meter |
| D. | Both (b) and (c) |
| Answer» E. | |
| 258. |
For measurement of surface temperature of solids the elements of RTD is usually in the shape of |
| A. | bar |
| B. | coil |
| C. | flat grid |
| D. | either (a) or (b) |
| Answer» D. either (a) or (b) | |
| 259. |
A 24 mm long conductor has a resistance of 128 Ω. The change in resistance is 13.3 Ω and change in length is 1.6 mm under tension. The gauge factor is |
| A. | 1.2 |
| B. | 1.6 |
| C. | 2.1 |
| D. | 2.6 |
| Answer» C. 2.1 | |
| 260. |
The advantage of LVDT over inductive bridge type transducer is that |
| A. | it gives high output for small changes in core position |
| B. | it can be used over a temperature range of - 265°C to 600°C |
| C. | it can measure displacement of moving object |
| D. | the error due to stray magnetic field is less |
| Answer» B. it can be used over a temperature range of - 265°C to 600°C | |
| 261. |
A voltage of about 200 V dc can be measured |
| A. | directly by dc potentiometer |
| B. | by dc potentiometer in conjunction with a volt ratio box |
| C. | a dc potentiometer in conjunction with a known resistance |
| D. | both (b) and (c) |
| Answer» C. a dc potentiometer in conjunction with a known resistance | |
| 262. |
Which of the following statement is correct for two wattmeters method of power measurement in 3 phase circuit? |
| A. | Power can be measured by this method only for star connected loads |
| B. | When two wattmeters have equal readings power factor is 0.5. |
| C. | When power factor is 1, one of the wattmeters readings is zero |
| D. | When the two wattmeter read equal and opposite, p.f. is zero. |
| Answer» E. | |
| 263. |
The response of a thermistor overs the whole of its temperatures range is |
| A. | linear |
| B. | non-linear |
| C. | almost linear |
| D. | either (a) or (c) |
| Answer» C. almost linear | |
| 264. |
Assertion (A): A radiation pyrometer is very suitable for high temperature measurement.Reason (R): When temperature is high, a physical contact between hot body and thermometer is not desirable. |
| A. | Both A and R are true and R is correct explanation of A |
| B. | Both A and R are true but R is not correct explanation of A |
| C. | A is true R is false |
| D. | A is false R is true |
| Answer» B. Both A and R are true but R is not correct explanation of A | |
| 265. |
In which of the transformer is the secondary nearly short circuited under normal operating conditions? |
| A. | CT |
| B. | PT |
| C. | Distribution transformer |
| D. | Power transformer |
| Answer» B. PT | |
| 266. |
Assertion (A): Wien bridge can be used for measuring frequency.Reason (R): A frequency meter for 50 Hz system has a frequency range of 40 to 60 Hz. |
| A. | Both A and R are true and R is correct explanation of A |
| B. | Both A and R are true but R is not correct explanation of A |
| C. | A is true R is false |
| D. | A is false R is true |
| Answer» D. A is false R is true | |
| 267. |
Assertion (A): Capacitance effect can be used to measure thickness of sheets, displacement and pressure.Reason (R): Capacitance between two plates depends on the area of plates, distance between plates and permittivity of medium. |
| A. | Both A and R are true and R is correct explanation of A |
| B. | Both A and R are true but R is not correct explanation of A |
| C. | A is true R is false |
| D. | A is false R is true |
| Answer» B. Both A and R are true but R is not correct explanation of A | |
| 268. |
If an inductance L is connected in one arm of bridge and resistance R1, R2, R3 in other three arms |
| A. | the bridge cannot be balanced |
| B. | the bridge can be balanced |
| C. | the bridge is balanced for some specified value of frequency |
| D. | the bridge is balanced for some specific values of R1, R2, R3 |
| Answer» B. the bridge can be balanced | |
| 269. |
The dead zone in a pyrometer is 0.125% of span. The calibration is 400°C to 1000°C. What temperature change might occur before it is detected. |
| A. | 0.125°C |
| B. | 0.75°C |
| C. | 0.4°C |
| D. | 1°C |
| Answer» C. 0.4°C | |
| 270. |
To measure dielectric loss you would use |
| A. | Anderson bridge |
| B. | Kelvin bridge |
| C. | Schering bridge |
| D. | Maxwell's bridge |
| Answer» D. Maxwell's bridge | |
| 271. |
Load cell uses |
| A. | piezoelectric crystal |
| B. | capacitor |
| C. | mutual inductance |
| D. | strain gauge |
| Answer» E. | |
| 272. |
The advantage of semiconductor strain gauge over resistance strain gauge is |
| A. | it is more sensitve |
| B. | it is more linear |
| C. | it is less temperature dependent |
| D. | it is cheaper |
| Answer» B. it is more linear | |
| 273. |
Insertion of a dielectric material between the plates of an air capacitor |
| A. | increases the capacitance |
| B. | decreases capacitance |
| C. | has no effect an capacitance |
| D. | increases breakdown voltage |
| Answer» B. decreases capacitance | |
| 274. |
A capacitance transducer can be used to measure |
| A. | thickness of sheet |
| B. | displacement |
| C. | level of fluids |
| D. | all of the above |
| Answer» E. | |
| 275. |
Which of the following devices should be used for accurate measurement of a low dc voltage? |
| A. | Small range moving coil voltmeter |
| B. | Dc potentiometer |
| C. | Small range thermocouple voltmeter |
| D. | Hot wire instrument |
| Answer» C. Small range thermocouple voltmeter | |
| 276. |
The input impedance of CRO is about |
| A. | zero |
| B. | 10 Ω |
| C. | 100 Ω |
| D. | one mega ohm |
| Answer» E. | |
| 277. |
A current of 3.18 A is flowing through resistance of 35.68 Ω. The voltage drop across resistance to the appropriate number of significant figures is |
| A. | 113.4624 V |
| B. | 113.462 V |
| C. | 113.46 V |
| D. | 113 V |
| Answer» E. | |
| 278. |
The 10 MHz in the specification of CRO means that |
| A. | the sweep frequency is 10 MHz |
| B. | the frequency of input signal should not be more than 10 MHz |
| C. | the vertical amplifier has been designed for 10 MHz |
| D. | none of the above |
| Answer» B. the frequency of input signal should not be more than 10 MHz | |
| 279. |
Kelvin's double bridge is used to measure low resistances because |
| A. | it has high sensitivity |
| B. | there is no thermoelectric emf |
| C. | resistance variation due to temperature |
| D. | effect of contact and lead resistances is eliminated |
| Answer» E. | |
| 280. |
The switch board instruments |
| A. | should be mounted in vertical position |
| B. | should be mounted in horizontal position |
| C. | should be mounted at about 45° |
| D. | should be mounted at about 80° |
| Answer» B. should be mounted in horizontal position | |
| 281. |
For measuring mutual inductance we can use |
| A. | Anderson bridge |
| B. | Maxwell's bridge |
| C. | Heaviside bridge |
| D. | Either (a) or (b) |
| Answer» D. Either (a) or (b) | |
| 282. |
Absolute instruments are used in |
| A. | laboratories |
| B. | industries |
| C. | power houses |
| D. | standard laboratories |
| Answer» E. | |
| 283. |
The power input and output in a device are 3650 W and 3385 W with each reading in doubt by ± 10 W. The percentage uncertainty in losses is |
| A. | ± 7.55% |
| B. | ± 3.77% |
| C. | ± 11.32% |
| D. | ± 15.09% |
| Answer» B. ± 3.77% | |
| 284. |
If the secondary winding of CT is opened when primary coil is carrying current |
| A. | transformer will burn immediately |
| B. | there will be weak flux density in core |
| C. | there will be very high induced voltage in secondary |
| D. | there will be high current in secondary |
| Answer» D. there will be high current in secondary | |
| 285. |
In a CRO, the time base signal is applied to |
| A. | X plates |
| B. | Y plates |
| C. | either X or Y plates |
| D. | alternately X and Y plates |
| Answer» B. Y plates | |
| 286. |
In order to achieve accuracy, the slide wire of a potentiometer should be |
| A. | as long as possible |
| B. | as short as possible |
| C. | neither too long nor too short |
| D. | very thin |
| Answer» B. as short as possible | |
| 287. |
A multimeter can be used as ohmmeter. |
| A. | True |
| B. | False |
| C. | May be True or False |
| D. | can't say |
| Answer» B. False | |
| 288. |
During testing of an energy meter, the energy recorded by meter was 0.05 kWh and correct energy was found to be 0.09 kWh. The error and correction respectively are |
| A. | -0.01 kWh and 0.01 kWh |
| B. | 0.01 kWh and -0.01 kWh |
| C. | -0.01 kWh and ± 0.01 kWh |
| D. | ± 0.01 kWh and 0.01 kWh |
| Answer» B. 0.01 kWh and -0.01 kWh | |
| 289. |
Wagner earthing device eliminates |
| A. | all stray capacitance in the circuit |
| B. | stray capacitances between components |
| C. | stray capacitance between detector terminal and ground |
| D. | mutual coupling between components |
| Answer» D. mutual coupling between components | |
| 290. |
For use at 50 Hz the range of scale of vibrating reed frequency meter is |
| A. | 25 - 75 Hz |
| B. | 40 - 60 Hz |
| C. | 47 - 53 Hz |
| D. | 42 - 58 Hz |
| Answer» D. 42 - 58 Hz | |
| 291. |
Two numbers are 131 ± 5 and 629 ± 3. The sum of the numbers with range of doubt is |
| A. | 760 ± 8 |
| B. | 760 ± 2 |
| C. | 760 + 8 |
| D. | 760 - 8 |
| Answer» B. 760 ± 2 | |
| 292. |
A sinusoidal ac voltage of amplitude 100 V is applied to a rectifying device which offers 10 Ω resistance in forward direction and infinite resistance in backward direction. A moving coil ammeter is also connected in the circuit. The reading of ammeter will be |
| A. | 10 A |
| B. | 5 A |
| C. | 3.185 A |
| D. | 14.14 A |
| Answer» D. 14.14 A | |
| 293. |
Two wattmeter method for 3 phase power measurement can be used only for |
| A. | balanced loads |
| B. | unbalanced loads |
| C. | both balanced and unbalanced loads |
| D. | star connected loads |
| Answer» D. star connected loads | |
| 294. |
In Weston synchronoscope the fixed coils are connected across |
| A. | bus bars |
| B. | incoming alternator |
| C. | lamp |
| D. | either (a) or (b) |
| Answer» C. lamp | |
| 295. |
Gauge factor of a strain gauge is |
| A. | unit change in resistance per unit change in length |
| B. | change in resistance per unit change in length |
| C. | unit change in length per unit change in resistance |
| D. | none of the above |
| Answer» B. change in resistance per unit change in length | |
| 296. |
For measuring temperatures below 800°C with high accuracy, the best instrument is |
| A. | optical pyrometer |
| B. | thermistor based thermometer |
| C. | GaAs junction diode thermometer |
| D. | platinum resistance thermometer |
| Answer» E. | |
| 297. |
An accelerometer has a seismic mass of 0.05 kg and spring constant of 3 x 10⁵ N/m. If maximum displacement of mass is ± 1 mm, the maximum acceleration which can be measured is |
| A. | 30 m/s² |
| B. | 60 m/s² |
| C. | 90 m/s² |
| D. | 120 m/s² |
| Answer» C. 90 m/s² | |
| 298. |
Assertion (A): A dc potentiometer measures the true open circuit emf of a source.Reason (R): At balance point, a dc potentiometer does not draw any current from the source. |
| A. | Both A and R are true and R is correct explanation of A |
| B. | Both A and R are true but R is not correct explanation of A |
| C. | A is true R is false |
| D. | A is false R is true |
| Answer» B. Both A and R are true but R is not correct explanation of A | |
| 299. |
A dynamometer wattmeter can be used for |
| A. | dc only |
| B. | ac only |
| C. | dc and 50 Hz ac |
| D. | dc and high frequency ac |
| Answer» D. dc and high frequency ac | |
| 300. |
If two time varying signals of equal magnitude and zero phase displacement are applied to X and Y plates respectively; of CRO, the display will be |
| A. | a straight line |
| B. | a circle |
| C. | an ellipse |
| D. | a square |
| Answer» B. a circle | |