MCQOPTIONS
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MCQOPTIONS
This section includes 256 Mcqs, each offering curated multiple-choice questions to sharpen your Chemical Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
Which of the following thermocouples has the least temperature measurement range ? |
| A. | Copper-constantan |
| B. | Chromel-alumel |
| C. | Platinum-platinum/rhodium |
| D. | Iron-constantan |
| Answer» B. Chromel-alumel | |
| 2. |
Which of the following thermocouples is capable of measuring a temperature of -50°C ? |
| A. | Platinum-platinum + rhodium |
| B. | Chromel-Alumel |
| C. | Iron-constantan |
| D. | Copper-constantan |
| Answer» B. Chromel-Alumel | |
| 3. |
Which of the following thermometers is not suitable for distant reading upto 60 metres ? |
| A. | Vapor pressure thermometer |
| B. | Mercury in glass thermometer |
| C. | Constant volume gas thermometer |
| D. | Resistance thermometer |
| Answer» C. Constant volume gas thermometer | |
| 4. |
Which of the systems having following transfer functions is stable ? |
| A. | 1/(s2 + 2) |
| B. | 1/(s2 – 2s + 3) |
| C. | 1/(s2 + 2s + 2) |
| D. | exp (-20s)/(s2 + 2s – 1) |
| Answer» D. exp (-20s)/(s2 + 2s – 1) | |
| 5. |
With increase in temperature, the electrical conductivity of the platinum used in the resistance thermometer ? |
| A. | Increases |
| B. | Decreases |
| C. | Remain constant |
| D. | Increases exponentially |
| Answer» C. Remain constant | |
| 6. |
Working principle of bimetallic thermometers is difference in linear co-efficient of thermal expansion of two strips of different metals welded together. Which of the following has the maximum thermal co-efficient of linear expansion ? |
| A. | Nickel |
| B. | Brass |
| C. | Chromel |
| D. | Invar |
| Answer» C. Chromel | |
| 7. |
Working principle of disappearing filament type optical pyrometer is based on the ________________? |
| A. | Wien’s law |
| B. | Seebeck effect |
| C. | Kirchoff’s law |
| D. | Peltier effect |
| Answer» B. Seebeck effect | |
| 8. |
Working principle of mercury in glass thermometer is based on the ______________ of mercury with increase in temperature? |
| A. | Increase of pressure |
| B. | Increase of thermal conductivity |
| C. | Volumetric expansion |
| D. | Differential linear expansion |
| Answer» D. Differential linear expansion | |
| 9. |
Working principle of mercury in glass thermometer is__________________? |
| A. | Volumetric expansion |
| B. | Pressure rise with temperature |
| C. | Linear expansion |
| D. | None of these |
| Answer» B. Pressure rise with temperature | |
| 10. |
Working principle of radiation pyrometer is based on the ________________? |
| A. | Wien’s law |
| B. | Kirchoff’s law |
| C. | Stefan-Boltzmann law |
| D. | Seebeck effect |
| Answer» D. Seebeck effect | |
| 11. |
Working principle of radiation pyrometer is based on the __________________? |
| A. | Wien’s law |
| B. | Kirchoff’s law |
| C. | Stefan Boltzmann law |
| D. | Seebeck effect |
| Answer» D. Seebeck effect | |
| 12. |
Zirconia probe is used for the continuous measurement of ______________ flue gases going out of the furnace? |
| A. | Oxygen in |
| B. | Carbon dioxide in |
| C. | Carbon monoxide in |
| D. | Temperature of |
| Answer» B. Carbon dioxide in | |
| 13. |
Zirconia probe is used for the measurement of___________________? |
| A. | Humidity of air |
| B. | % CO2 in flue gas |
| C. | % O2 in flue gas |
| D. | Speed of a submarine |
| Answer» D. Speed of a submarine | |
| 14. |
Which of the following relates the absorption & evolution of heat at the junctions of a thermocouple to the current flow in the circuit ? |
| A. | Seebeck effect |
| B. | Peltier effect |
| C. | Joule heating effect |
| D. | Thomson effect |
| Answer» C. Joule heating effect | |
| 15. |
Which of the following is not suitable for measuring the temperature of a red hot object in the range of 800 – 1600°C ? |
| A. | Optical pyrometer |
| B. | Radiation pyrometer |
| C. | Photoelectric pyrometer |
| D. | Thermocouples |
| Answer» E. | |
| 16. |
Which of the following is a ‘contact’ pyrometer ? |
| A. | Resistance pyrometer |
| B. | Optical pyrometer |
| C. | Radiation pyrometer |
| D. | Infra red pyrometer |
| Answer» B. Optical pyrometer | |
| 17. |
Which of the following flow-metering instruments is an areameter ? |
| A. | Venturimeter |
| B. | Rotameter |
| C. | Pitot tube |
| D. | Hot wire anemometer |
| Answer» C. Pitot tube | |
| 18. |
Which of the following cannot measure a temperature of 1600°C ? |
| A. | Platinum resistance thermometer |
| B. | Thermocouple |
| C. | Photo-electric pyrometer |
| D. | Radiation pyrometer |
| Answer» B. Thermocouple | |
| 19. |
Which of the following can measure temperatures in the range of – 20 to 300°C ? |
| A. | Mercury in glass thermometer |
| B. | Vapor pressure thermometer |
| C. | Resistance thermometer |
| D. | None of these |
| Answer» E. | |
| 20. |
Which is the strongest paramagnetic gas ? |
| A. | CO2 |
| B. | O2 |
| C. | NO |
| D. | NO2 |
| Answer» C. NO | |
| 21. |
When the damping co-efficient (ξ) is unity, the system is __________________? |
| A. | Overdamped |
| B. | Critically damped |
| C. | Underdamped |
| D. | Highly fluctuating |
| Answer» C. Underdamped | |
| 22. |
What is the overall transfer function (C/R) of the following block diagram if G = G1. G2. G3 and H = H1.H2 ? |
| A. | 1/(1 + GH) |
| B. | G/(1 + GH) |
| C. | H/(1 + GH) |
| D. | G/(1 – GH) |
| Answer» C. H/(1 + GH) | |
| 23. |
What is the Laplace transform of impulse input having magnitude „X‟ ? |
| A. | X |
| B. | X2 |
| C. | 1/X |
| D. | 1 |
| Answer» E. | |
| 24. |
Water is flowing through a series of four tanks and getting heated as shown in figure. It is desired to design a cascade control scheme for controlling the temperature of water leaving the tank 4 as there is a disturbance in the temperature of a second stream entering the tank 2. Select the best place to take the secondary measurement for the second loop? |
| A. | Tank 1 |
| B. | Tank 2 |
| C. | Tank 3 |
| D. | Tank 4 |
| Answer» D. Tank 4 | |
| 25. |
Water is entering a storage tank at a temperature T0 and flow rate Q0 and leaving at a flow rate Q and temperature T. There are negligible heat losses in the tank. The area of cross-section of the tank is A0. The model that describes the dynamic variation of temperature of water in the tank with time is given as________________? |
| A. | Q0(T0 – T) = Ac . h (dT/dt) |
| B. | Q0T0 – QT = Ac . h (dT/dt) |
| C. | Q(T0 – T) = Ac . h (dT/dt) |
| D. | Q(T0 – T) = Ac . (dTH/dt) |
| Answer» B. Q0T0 – QT = Ac . h (dT/dt) | |
| 26. |
Volumetric expansion is the working principle of the ______________ thermometers? |
| A. | Mercury in glass |
| B. | Constant volume gas |
| C. | Vapor pressure |
| D. | Bimetallic |
| Answer» B. Constant volume gas | |
| 27. |
Very low pressure is expressed in microns (μ), which is equal to ____________ mm of Hg column (absolute) at 0°C? |
| A. | 0.0001 |
| B. | 0.001 |
| C. | 0.01 |
| D. | 0.1 |
| Answer» C. 0.01 | |
| 28. |
Vapour actuated pressure spring thermometer does not require ambient temperature compensation. Ambient temperature compensation is provided in gas or liquid expansion pressure spring thermometer by__________________? |
| A. | Making the volume of thermometer bulb as large as conveniently possible |
| B. | Reducing the volume of the capillary to a minimum |
| C. | Reducing the volume of the receiving element to a minimum |
| D. | All A , B & C. |
| Answer» E. | |
| 29. |
Use of I-control along with P-control facilitates ? |
| A. | Elimination of offset |
| B. | Reduction of offset |
| C. | Reduction of stability time |
| D. | None of these |
| Answer» B. Reduction of offset | |
| 30. |
Typical specifications for design stipulates the gain margin and phase margin to be respectively__________________? |
| A. | > 1.7 and > 30° |
| B. | 30° |
| C. | < 1.7 and 1.7 and < 30° |
| Answer» B. 30° | |
| 31. |
Turbine flow meters are suitable for_________________? |
| A. | Very limited flow ranges |
| B. | Cryogenic flow measurements |
| C. | Aerospace and in air borne applications |
| D. | Both B. and C. |
| Answer» E. | |
| 32. |
Transfer function of transportation lag is___________________? |
| A. | eTS |
| B. | e-TS |
| C. | 1/(Ts + 1) |
| D. | None of these |
| Answer» C. 1/(Ts + 1) | |
| 33. |
To increase the speed of response of a pressure spring liquid or gas expansion thermometer, the clearance space between the thermometer bulb and the thermal well should not be filled with ________________? |
| A. | Air |
| B. | A metal powder or graphite |
| C. | Oil |
| D. | Mercury |
| Answer» B. A metal powder or graphite | |
| 34. |
Time constant is the __________________? |
| A. | Time taken by the controlled variable to reach 63.2% of its full change |
| B. | Same as transportation lag |
| C. | Same as dead time |
| D. | Time required by the measured variable to reach 63.2% of its ultimate change |
| Answer» B. Same as transportation lag | |
| 35. |
_______________ thermometer cannot measure sub-zero (< 0° C) temperature ? |
| A. | Mercury in glass |
| B. | Bimetallic |
| C. | Vapor pressure |
| D. | Resistance |
| Answer» C. Vapor pressure | |
| 36. |
Thermodynamic Celsius scale of temperature measurement is________________? |
| A. | Defined on the basis of melting point of ice and evaporation temperature of water vapor |
| B. | Defined on the basis of melting point of ice and condensation temperature of water vapor |
| C. | Having an interval of 100° between ice point to steam point |
| D. | Both B. and C. |
| Answer» E. | |
| 37. |
Thermocouple is suitable for measuring_________________? |
| A. | Liquid temperatures only |
| B. | Very high temperatures only |
| C. | Very low temperatures only |
| D. | Both high and low temperatures |
| Answer» E. | |
| 38. |
Thermocouple in a thermal well behaves as a true ________________? |
| A. | First order system |
| B. | Second order system (overdamped) |
| C. | Multiple first order system |
| D. | Second order system (underdamped) |
| Answer» D. Second order system (underdamped) | |
| 39. |
Thermistors are used in ____________ devices? |
| A. | Voltage measuring |
| B. | Temperature measuring |
| C. | Temperature compensating |
| D. | Both B. & C. |
| Answer» E. | |
| 40. |
Thermistors which have a very high temperature co-efficient of resistivity belong to the class of solid called________________? |
| A. | Dielectrics |
| B. | Insulators |
| C. | Semi conductors |
| D. | Conductors |
| Answer» D. Conductors | |
| 41. |
Thermistor, which has high temperature co-efficient of resistivity, is used as the sensing element in resistance thermometer. It is a/an ? |
| A. | Insulator |
| B. | Conductor |
| C. | Solid semi-conductor |
| D. | Liquid semi-conductor |
| Answer» D. Liquid semi-conductor | |
| 42. |
Thermistors are made of__________________? |
| A. | Ultra pure metals |
| B. | Metal oxides |
| C. | Iron-copper alloys |
| D. | Nickel-chromium alloys |
| Answer» C. Iron-copper alloys | |
| 43. |
Thermal wells used in temperature measurements should have __________________? |
| A. | Very thick walls |
| B. | Low emissivity |
| C. | Polished surface |
| D. | High transmissivity of radiation |
| Answer» E. | |
| 44. |
Thermal wells are used in the temperature measurement to____________________? |
| A. | Guard against corrosive and oxidising action on thermocouple materials |
| B. | Reduce measuring lag |
| C. | Increase the fidelity |
| D. | Increase the sensitivity |
| Answer» B. Reduce measuring lag | |
| 45. |
Thermal well made of _____________ gives the fastest speed of response, while measuring temperature by thermocouples? |
| A. | Steel |
| B. | Vycor (a glass) |
| C. | Nichrome |
| D. | Inconel |
| Answer» C. Nichrome | |
| 46. |
Thermal conductivity cell is the primary element of a/an _____________ analyser? |
| A. | Oxygen |
| B. | Carbon dioxide |
| C. | Carbon monoxide |
| D. | Sulphur dioxide |
| Answer» C. Carbon monoxide | |
| 47. |
Thermal conductivity measurement com-prises the working principle of a_________________? |
| A. | CO2 analyser |
| B. | Polarimeter |
| C. | Spectrometer |
| D. | Chromatograph |
| Answer» B. Polarimeter | |
| 48. |
Thermal conductivity measurement is used for the determination of________________? |
| A. | O2 percentage in the flue gas |
| B. | Specific gravity of petrofuels |
| C. | Composition of an alloy |
| D. | CO2 percentage in the flue gas |
| Answer» E. | |
| 49. |
The unit step response of the transfer function (2s – 1)/[(3s + 1) (4s + 1)] reaches its final steady state asymptotically after _____________? |
| A. | A monotonic increase |
| B. | A monotonic decrease |
| C. | Initially increasing and then decreasing |
| D. | Increasing decreasing and then increasing |
| Answer» B. A monotonic decrease | |
| 50. |
The unit step response of the transfer function 1/(s2 + 2s + 3) _______________________? |
| A. | Has a non-zero slope at the origin |
| B. | Has a damped oscillatory characteristics |
| C. | Is overdamped |
| D. | Is unstable |
| Answer» C. Is overdamped | |