Description : Measuring with a 30 m chain, 0.01 m too short, introduces (A) Positive compensating error (B) Negative compensating error (C) Positive cumulative error (D) Negative cumulative error
Last Answer : (C) Positive cumulative error
Description : Silicon diodes designed for a specific reverse breakdown voltage, become useful as an electronic power supply voltage regulator, called _____________. A. tunnel diodes B. hot-carrier diodes C. compensating diodes D. Zener diodes
Last Answer : Answer: D
Description : ___ sensors include thermocouples, thermistors, resistor temperature detectors (RTDs) and integratd circuits (ICs). A. Smoke Sensor B. Temperature Sensor C. IR Sensor D. Proximity Sensor
Last Answer : B. Temperature Sensor
Description : What type of temperature coefficient do thermistors have? (1) Positive (2) Negative (3) Either positive or negative (4) None of these
Last Answer : Either positive or negative type of temperature coefficient do thermistors have.
Description : Protective relays are devices that detect abnormal conditions in electrical circuits by measuring (a) current during abnormal condition (b) voltage during abnormal condition (c) constantly the electrical quantities which differ during normal and abnormal conditions (d) none of the above
Last Answer : (c) constantly the electrical quantities which differ during normal and abnormal conditions
Description : What does the arrangement at coordinates '62E' shown in the illustration represent? EL-0099 A. Position recording drum and stylus B. Temperature compensating thyristor C. Miniature bridge rectifier D. Twisted wire pair within a shield
Description : A thin, flat & square plate measuring 2 m 2 m is freely hanging in ambient air at 25°C. It is exposed to the solar radiation falling on one side of the plate at the rate of 500 W/m2. The plate temperature will ... heat transfer co-efficient is __________ W/m2 °C. (A) 50 (B) 100 (C) 150 (D) 200
Last Answer : (B) 100
Description : What type of material is used in the construction of bolometers and thermistors?
Last Answer : Temperature-sensitive material that exhibits a large negative temperature coefficient.
Description : Hall effect is associated with (A) Conductors. (B) Semiconductors. (C) Thermistors. (D) Solders.
Last Answer : (B) Semiconductors.
Description : What are the uses of Thermistors ?
Last Answer : Thermistors are frequently used in electronic circuits in which it is desired to provide temperature measurement, temperature control, and temperature compensation.
Description : Compare between RDTs and Thermistors.
Last Answer : RTD Thermistor Made of metals like copper, platinum, nickel and tungsten. Made of metallic oxides such as cobalt, manganese, nickel etc. Have positive temperature coefficient of resistance ... are quite small in size and in shapes like washer, bead, probe, disc, etc.
Description : State the working principle of thermistors
Last Answer : A thermistor is a type of resistor whose resistance is dependent on temperature. Working principle: Whenever there is a change in temperature, the resistance of some semiconductors change . In case of ... . In case of NTC type, the resistance of the thermistor decreases with increase in temperature.
Description : List applications of thermocouple and thermistors.
Last Answer : Applications of Thermistors: 1. Widely used in the applications of the range from - 60oC to + 15oC. 2. Used as a sensor in liquid level, pressure, flow measurement systems. 3. Used for measurement ... 2. It is used for temperature measurement in cryogenic range. 3. It is used for flow measurement.
Description : Which of the following materials is used in the construction of thermistors? A) Pure metal B) Pure semiconductor C) Pure insulator D) Sintered mixture of metal oxides
Last Answer : Which of the following materials is used in the construction of thermistors? A) Pure metal B) Pure semiconductor C) Pure insulator D) Sintered mixture of metal oxides
Description : Which one of the following statements for a dc machine which is provided with inter pole winding (IW) as well as compensating winding (CW) is correct a) Both IW and CW are connected in ... parallel with Armature winding d) CW connected in series but IW is connected in parallel with Armature winding
Last Answer : Ans: Both IW and CW are connected in series with Armature winding
Description : Which of the listed devices may be installed on a large diesel-electric alternating current propulsion generator? A. Temperature detector coils inserted in the stator slots for measuring stator temperature. B. ... . C. Electric space heaters to prevent condensation of moisture. D. All of the above.
Description : Which of the listed devices may be installed on a large turbo-electric alternating current propulsion generator? A. Temperature detector coils inserted in the stator slots for measuring stator temperature. B. A ... . C. Electric space heaters to prevent condensation of moisture. D. All of the above.
Description : List any four temperature measuring devices.
Last Answer : Temperature measuring devices : RTD, thermocouple, thermistor, thermometer, bimetallic thermometer, radiation pyrometer, optical pyrometer
Description : Give the names of different electrical temperature measuring devices.
Last Answer : Electrical temperature measuring devices: RTD, thermocouple, thermistor
Description : Out of the following flow measuring devices, which one incurs themaximum installation cost as well as pressure loss? (A) Flow nozzle (B) Venturimeter (C) Rotameter (D) Orificemeter
Last Answer : (B) Venturimeter
Description : Which of the following flow measuring devices is an area meter? (A) Venturimeter (B) Orificemeter (C) Anemometer (D) Rotameter
Last Answer : (D) Rotameter
Description : Where a thermal-acting breaker is required to be used in an area of unusually high, low, or constantly fluctuating temperatures, an ambient compensating element must be used. This element consists of ... arm B. conical spring on the contact arm C. second bimetal element D. second electromagnet
Last Answer : Answer: C
Description : What are the two compensating techniques used in frequency compensation?
Last Answer : Two types of compensating techniques are used, they are, a. External compensation b. Internal compensation
Description : A uniform slope was measured by the method of stepping. If the difference in level between two points is 1.8 m and the slope distance between them is 15 m, the error is approximately equal to (A) Cumulative, + 0.11 m (B) Compensating, ± 0.11 m (C) Cumulative, - 0.11 m (D) None of these
Last Answer : (A) Cumulative, + 0.11 m
Description : The incisal guidance on the articulator is the:** A. Mechanical equivalent of horizontal and vertical overlap of upper and lower incisors B. Mechanical equivalent of the compensating curve C. Same as condylar guidance D. Estimated by the equation: Incisal guidance = 1/8 of condylar guidance
Last Answer : A. Mechanical equivalent of horizontal and vertical overlap of upper and lower incisors
Description : Second glass plate in Michelson ‘s Interferometer is known as A. Extra glass plate C. Simple Glass Plate B. Compensating glass plate D. None of these
Last Answer : B. Compensating glass plate
Description : Which of the following methods may be adopted to reduce the effects of armature reaction ? (a) Increase in length of air gap at pole tips (b) Increasing reluctance of pole tips (c) Compensating windings (d) Interpoles (e) All of the above
Last Answer : (e) All of the above
Description : Consider the following statements 1) The compensating coil of a low power factor wattmeter compensates the effect of the impedance of the current coil ii) The compensating coil of a low power factor wattmeter compensates the effect ... C) Both (i) and (ii) are true D) Both (i) and (ii) are false
Last Answer : A
Description : Under which of the following conditions is a DC motor provided with compensating winding used? 1. Wide range of speed control above normal 2. Wide range of steady load variation with no speed control 3. Wide range of rapid variation in ... (a) 1, 2 and 3 (b) 2 and 3 (c) 1 and 2 (d) 1 and 3
Last Answer : Under which of the following conditions is a DC motor provided with compensating winding used? 1. Wide range of speed control above normal 2. Wide range of steady load variation with no speed control 3. Wide range of rapid variation ... (a) 1, 2 and 3 (b) 2 and 3 (c) 1 and 2 (d) 1 and 3
Last Answer : The number of conductors of the compensating winding in a D.C. machine is always less than the number of armature conductors per pole.
Last Answer : In a low power factor wattmeter the compensating coil is connected in series with pressure coil.
Last Answer : Compensating windings are used in D.C. generators to neutralise the cross-magnetising effect of the armature reaction.
Description : In case of conductively compensated D.C. series motors, the compensating winding is provided?
Last Answer : In case of conductively compensated D.C. series motors, the compensating winding is provided in series with armature winding.
Last Answer : In A.C. series motor compensating winding is employed to reduce sparking at the brushes.
Description : You have installed a Zener diode in parallel with a load. While measuring the voltage across the Zener diode it is found that it does not change as the current through the load increases. This means that the ... is working as it should B. is shorted C. is open D. does not regulate as it should
Last Answer : Answer: A
Description : __________ calorimeter is normally used for measuring the dryness fraction of steam, when it is very low. (A) Bucket (B) Throttling (C) Separating (D) A combination of separating & throttling
Last Answer : (D) A combination of separating & throttling
Description : __________ glass is used in the mercury in glass thermometer meant for measuring a temperature of 500°C. (A) Borosilicate (B) High silica (C) Supermax (D) Lead
Last Answer : (C) Supermax
Description : When troubleshooting a lead-acid storage battery, a weak or dead cell is best detected by _________________. A. measuring and comparing all cells' specific gravity B. taking an open circuit ... electrolyte levels of each cell D. taking each cell's temperature with a calibrated mercury thermometer
Description : A temperature instrumentation system for an engine room console consists of a resistance temperature detector (RTD), a measuring bridge circuit, and a meter (or alarm circuit).Which of the following ... is zero. D. The input voltage of the resistance bridge is the constant temperature signal.
Description : Name the instruments used for measuring each of the following: (i) Pressure (ii) Voltage (iii) Purity of milk (iv) Temperature (v) Velocity of wind
Last Answer : Answers: (i). Barometer (ii). Voltmeter (iii). Lactometer (iv). Thermometer (v). Anemometer
Description : Why it is important that hand tools and measuring devices are wiped down and lubricated after use?
Last Answer : Taking care of your tools so they perform as intended and last alifetime is important. A good tradesman will keep his/her toolsclean and in excellant working condition. Good tools are expensive!Dirty, unkept tools are a reflection on the tradesman's quality ofwork and people do notice.
Description : What are measuring devices with lasers used for with earthquakes?
Last Answer : Laser-ranging devices us laser beams to detect the faultmovements that cause earthquakes.
Description : What arc the errors occurring in measuring devices due to stray magnetic field and temp '? Explain how to compensate them.
Last Answer : 1. Error due to stray magnetic fields- Main magnetic field gets disturbed by external magnetic fields known as stray magnetic fields. 2. Compensation technique To avoid this error, ... resistance alloy having a negligible resistance temp coefficient in the ratio of 1:10 for pressure coil
Last Answer : Protective relays are devices that detect abnormal conditions in electrical circuits by measuring constantly the electrical quantities which differ during normal and abnormal conditions.
Description : __________ is used for measuring the static pressure exerted on the wall by a fluid flowing parallel to the wall in a pipeline. (A) Venturimeter (B) Pressure gauge (C) Pitot tube (D) Orificemeter
Last Answer : (C) Pitot tube
Description : In a/an __________, the flow rate of fluids is obtained by measuring the difference between the impact and the static pressure. (A) Rotameter (B) Pitot tube (C) Venturimeter (D) Flow nozzle
Last Answer : (B) Pitot tube
Description : Dryness fraction of wet steam is defined as the ratio of mass of vapour in the mixture to the mass of mixture __________ calorimeter is not used for measuring the dryness fraction of steam. (A) Bomb (B) Separating (C) Bucket (D) Throttling
Last Answer : A) Bomb
Description : A short in the shunt field of a DC motor is best located by _____________. A. visual inspection of the commutator B. applying AC voltage to each field coil and measuring the voltage drop across ... using a growler and hacksaw blade D. isolating each coil from the others and using a megohmmeter
Last Answer : Answer: B
Description : When using a multimeter for resistance measurements, it should be calibrated by clipping the loose ends of the leads together and _____________. A. setting the instrument pointer at 'zero' ohms B. ... the plus and minus terminals D. using a special purpose resistance measuring instrument (a bridge)
Description : When voltage increases then current also increases then what is the need of over voltage relay and over current relay? Can we measure over voltage and over current by measuring current only?
Last Answer : No. We can't sense the over voltage by just measuring the current only because the current increases not only for over voltages but also for under voltage (As most of the loads are non-linear in ... So, for a better protection of the system. It should have both over voltage & over current relay.