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This section includes 830 Mcqs, each offering curated multiple-choice questions to sharpen your Chemical Engineering knowledge and support exam preparation. Choose a topic below to get started.
801. |
An amplitude ratio of 0.1 corresponds to __________ decibels. |
A. | 20 |
B. | -20 |
C. | 10 |
D. | -10 |
Answer» C. 10 | |
802. |
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. | |
803. |
The function of a transducer is to |
A. | modify the input signal. |
B. | amplify the input signal. |
C. | convert the primary signal into a more useful quantity, usually an electric impulse. |
D. | codify/decodify the input signal. |
Answer» D. codify/decodify the input signal. | |
804. |
A typical example of a physical system with under damped characteristic is a |
A. | U-tube manometer. |
B. | spring loaded diaphragm valve. |
C. | CSTR with first order reaction. |
D. | thermocouple kept immersed in a liquid filled thermowell. |
Answer» C. CSTR with first order reaction. | |
805. |
The temperature of tempering oil baths maintained at 400°C during heat treatment of steel is measured by a/an __________ thermocouple. |
A. | chromel-alumel |
B. | iron-constantan |
C. | platinum-platinum/rhodium |
D. | none of these. |
Answer» C. platinum-platinum/rhodium | |
806. |
The Laplace transform of exp(at), where a > 0, is defined only for the Laplace parameter, s > a since |
A. | the function is exponential. |
B. | the Laplace transform of integral of exp(at) has finite values only for s > a. |
C. | the Laplace transform integral of exp(at) has initial values only for s > a. |
D. | the function exp(at) is piece-wise continuous only for s > a. |
Answer» C. the Laplace transform integral of exp(at) has initial values only for s > a. | |
807. |
A mercury thermometer can not be used to measure the temperature below the freezing point of mercury, which is __________ °C. |
A. | -38.9 |
B. | -11.9 |
C. | -60.9 |
D. | -80.9 |
Answer» B. -11.9 | |
808. |
Mass spectrometer is used for the composition analysis of |
A. | alloys |
B. | solids |
C. | isotopes |
D. | none of these |
Answer» D. none of these | |
809. |
Which of the following thermocouples can measure the maximum temperature ? |
A. | Platinum-rhodium |
B. | Tungsten-molybdenum |
C. | Chromel-alumel |
D. | Iron-constantan |
Answer» C. Chromel-alumel | |
810. |
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). | |
811. |
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 | |
812. |
Change of angle of refraction with composition comprises the working principle of a |
A. | polarimeter |
B. | polarograph |
C. | spectrometer |
D. | refractrometer |
Answer» E. | |
813. |
Thermal conductivity measurement com-prises the working principle of a |
A. | CO2 analyser |
B. | polarimeter |
C. | spectrometer |
D. | chromatograph |
Answer» B. polarimeter | |
814. |
The symbol for "capillary line" in instrumentation diagram is |
A. | |
B. | |
C. | |
D. | |
Answer» C. | |
815. |
The temperature range for which copper resistance thermometer can be used is __________ °C |
A. | 0 to 150 |
B. | -200 to 150 |
C. | 350 to 750 |
D. | 500 to 900 |
Answer» C. 350 to 750 | |
816. |
Which of the following is not the triple point of water ? |
A. | 32°R |
B. | 273°K |
C. | 492°R |
D. | 32°F |
Answer» B. 273¬∞K | |
817. |
Which of the following is a desirable characteristic of an instrument ? |
A. | High drift |
B. | High fidelity |
C. | High measuring lag |
D. | Poor reproducibility |
Answer» C. High measuring lag | |
818. |
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. | |
819. |
Compositional analysis of __________ is done using mass spectrometer. |
A. | an isotope |
B. | natural gas |
C. | a solid |
D. | an alloy |
Answer» B. natural gas | |
820. |
Pyrometry refers to the measurement of temperature |
A. | with the mercurial thermometer upto 350°C. |
B. | directly. |
C. | which is of higher magnitude. |
D. | all (a), (b) & (c). |
Answer» D. all (a), (b) & (c). | |
821. |
Which of the following is the dynamic characteristics of an instrument ? |
A. | Reproducibility |
B. | Sensitivity |
C. | Dead zone |
D. | Fidelity |
Answer» E. | |
822. |
The __________ of a vapor pressure thermometer is a secondary element. |
A. | pointer |
B. | Bourdon tube |
C. | bulb |
D. | none ofthese |
Answer» C. bulb | |
823. |
Load cells are used for the measurement of |
A. | stress |
B. | weight |
C. | strain |
D. | velocity |
Answer» C. strain | |
824. |
Typical specifications for design stipulates the gain margin and phase margin to be respectively |
A. | > 1.7 and > 30° |
B. | < 1.7 and > 30° |
C. | < 1.7 and < 30° |
D. | > 1.7 and < 30° |
Answer» B. < 1.7 and > 30¬∞ | |
825. |
A non-linear chemical system is exemplified by a/an |
A. | isothermal CSTR |
B. | mixer |
C. | non-isothermal CSTR |
D. | none of these |
Answer» D. none of these | |
826. |
Which of the following measurements can be made by the measurement of emf ? |
A. | pH value |
B. | Degree of hydrolysis |
C. | Composition of complex ions |
D. | All (a), (b) & (c) |
Answer» E. | |
827. |
Pick out the one which is a first order instrument. |
A. | Mercury in glass thermometer (without any covering or air gap). |
B. | Bare metallic thermometer. |
C. | Bare vapor pressure thermometer. |
D. | All (a), (b) and (c). |
Answer» E. | |
828. |
The time constant of a unity gain, first order plus time delay process is 5 min. If the phase lag at a frequency of 0.2 rad/min is 60°, then the dead time (in minutes) is |
A. | 5π/12 |
B. | π/6 |
C. | π/12 |
D. | π/3 |
Answer» B. œÄ/6 | |
829. |
Temperature measuring instruments are standardised mostly with __________ points of pure substances. |
A. | melting |
B. | boiling |
C. | both (a) & (b) |
D. | neither (a) nor (b) |
Answer» D. neither (a) nor (b) | |
830. |
Which of the following is an undesirable dynamic characteristic of an instrument ? |
A. | Reproducibility |
B. | Dead zone |
C. | Time lag |
D. | Static error |
Answer» D. Static error | |