MCQOPTIONS
Saved Bookmarks
MCQOPTIONS
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.
| 601. |
The transfer function for a P-D controller is |
| A. | Kc(1+τD s) |
| B. | Kc(1 +1/τD s) |
| C. | Kc τD s |
| D. | Kc/τD s |
| Answer» B. Kc(1 +1/œÑD s) | |
| 602. |
Characteristic equation is the denominator of __________ loop transfer function. |
| A. | open |
| B. | closed |
| C. | both (a)and (b) |
| D. | neither (a) nor (b) |
| Answer» C. both (a)and (b) | |
| 603. |
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-l) |
| Answer» D. exp(-20s)/(s2 + 2s-l) | |
| 604. |
Magnetic flowmeters are generally not used for the velocity/flow measurement of hydrocarbons due to their |
| A. | low thermal conductivity. |
| B. | low electrical conductivity. |
| C. | high viscosity index. |
| D. | low flash point. |
| Answer» C. high viscosity index. | |
| 605. |
Which thermocouple can be used to measure a temperature of around 1400°C ?$ |
| A. | Copper-constantan |
| B. | Aluminium-chromel |
| C. | Platinum-platinum+rhodium |
| D. | None of these |
| Answer» D. None of these | |
| 606. |
Bourdon gauges are used for measuring pressure (kg/cm2 ) |
| A. | < atmospheric |
| B. | > 2 (gauge) |
| C. | < 2 (gauge) |
| D. | > 10 (absolute) |
| Answer» C. < 2 (gauge) | |
| 607. |
What is the dynamic error in a critically damped second order instrument for a ramp input (At) ? |
| A. | 0.5 AT |
| B. | 2 AT |
| C. | AT |
| D. | 1.5 AT |
| Answer» C. AT | |
| 608. |
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. | |
| 609. |
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 | |
| 610. |
Reset rate is the another term used for __________ time. |
| A. | dead |
| B. | integral |
| C. | derivative |
| D. | none of these |
| Answer» C. derivative | |
| 611. |
Liquid flow rate in a small channel is best measured by a/an |
| A. | weir |
| B. | pitot tube |
| C. | vane meter |
| D. | venturimeter |
| Answer» C. vane meter | |
| 612. |
In a shell and tube heat exchanger, the outlet temperature of heating/cooling fluid is the __________ variable. |
| A. | load |
| B. | manipulated |
| C. | controlled |
| D. | none of these |
| Answer» D. none of these | |
| 613. |
Phase margin is equal to |
| A. | 180° - phase lag |
| B. | phase lag - 180° |
| C. | phase lag + 180° |
| D. | phase lag + 90° |
| Answer» B. phase lag - 180¬∞ | |
| 614. |
Out of the following themocouple wire insulating material, the highest temperature rating is for |
| A. | teflon |
| B. | ceramic fibre |
| C. | asbestos |
| D. | fibre glass |
| Answer» C. asbestos | |
| 615. |
Find the ultimate gain and frequency for a proportional controller in the case of a process having the transfer function Gp(s) = 1/(4s + 1)(2s + 1)(s + 1). |
| A. | w = 1/14, Kc = 45/714 |
| B. | w = 7/6, Kc = 46/3 |
| C. | w = 1, Kc = 13 |
| D. | w = 7/8, Kc = 45/4 |
| Answer» C. w = 1, Kc = 13 | |
| 616. |
Which of the following flow-metering instru-ments is an areameter ? |
| A. | Venturimeter |
| B. | Rotameter |
| C. | Pitot tube |
| D. | Hot wire anemometer |
| Answer» C. Pitot tube | |
| 617. |
According to Bode stability criterian, a system is unstable, if the open loop frequency response exhibits an amplitude ratio exceeding unity at frequency for which phase lag is |
| A. | 0° |
| B. | 45° |
| C. | 90° |
| D. | 180° |
| Answer» E. | |
| 618. |
For a feed back control system to be stable, the |
| A. | roots of the characteristic equation should be real. |
| B. | poles of the closed loop transfer function should lie in the left half of the complex plane. |
| C. | Bode plots of the corresponding open loop transfer function should monotoni-cally decrease. |
| D. | poles of the closed loop transfer function should lie in the right half of the complex plane. |
| Answer» C. Bode plots of the corresponding open loop transfer function should monotoni-cally decrease. | |
| 619. |
Bimetal strips are not used in |
| A. | bimetallic thermometers. |
| B. | thermocouples. |
| C. | thermostats. |
| D. | relays for opening & closing of electrical circuits. |
| Answer» C. thermostats. | |
| 620. |
In Bode plot, Φ vs ω is plotted on a/an __________ graph paper.$ |
| A. | log-log |
| B. | ordinary |
| C. | semi-log |
| D. | triangular |
| Answer» B. ordinary | |
| 621. |
The frequency at which maximum amplitude ratio is attained is called the __________ frequency. |
| A. | corner |
| B. | resonant |
| C. | cross-over |
| D. | natural |
| Answer» C. cross-over | |
| 622. |
A bimetallic thermometer as compared to industrial mercury in glass thermometer has almost the same |
| A. | temperature measuring range (- 40°C to 450°C). |
| B. | accuracy (± 1% of span). |
| C. | speed of response. |
| D. | all a, b & c. |
| Answer» E. | |
| 623. |
Measurement of pressure in ammonia reactor is done by |
| A. | Bourdon gauge |
| B. | U-tube manometer |
| C. | Inclined tube manometer |
| D. | Pirani guage |
| Answer» B. U-tube manometer | |
| 624. |
Which of the following judges the accuracy of an instrument ? |
| A. | Dead zone |
| B. | Drift |
| C. | Static error |
| D. | None of these |
| Answer» D. None of these | |
| 625. |
The __________ of the fluid contained in the temperature sensing element (i.e., bulb) of filled system thermometers changes with change in temperature. |
| A. | pressure |
| B. | volume |
| C. | viscosity |
| D. | all (a), (b) and (c) |
| Answer» E. | |
| 626. |
A pyranometer is an instrument used for measuring the |
| A. | beam radiation. |
| B. | global radiation. |
| C. | bright sunshine period. |
| D. | none of these. |
| Answer» C. bright sunshine period. | |
| 627. |
In a shell and tube heat exchanger, the inlet temperature of heating/cooling fluid is the __________ variable. |
| A. | load |
| B. | manipulated |
| C. | controlled |
| D. | none of these |
| Answer» B. manipulated | |
| 628. |
Continuous flue gas analyser makes use of paramagnetic properties of some of its constituents, which move towards the strongest part of the magnetic field thus displacing diamagnetic gases. Which of the following gases is diamagnetic ? |
| A. | CO2 |
| B. | O2 |
| C. | NO |
| D. | NO2 |
| Answer» B. O2 | |
| 629. |
"An emf of the order of mV is generated when two solutions of different hydrogen ion concentration are separated by a thin glass wall". This is the working principle of a |
| A. | pH meter |
| B. | polarimeter |
| C. | chromatograph |
| D. | polarograph |
| Answer» B. polarimeter | |
| 630. |
A simple pitot tube measures the |
| A. | average velocity |
| B. | maximum velocity |
| C. | point velocity |
| D. | static pressure |
| Answer» E. | |
| 631. |
Dome temperature of blast furnace stove is most accurately measured by a |
| A. | radiation pyrometer. |
| B. | platinum-platinum/rhodium ther-mocuple. |
| C. | iron-constantan thermocouple. |
| D. | platinum resistance thermometer. |
| Answer» C. iron-constantan thermocouple. | |
| 632. |
Feed forward controller accounts for the __________ changes. |
| A. | set point |
| B. | load |
| C. | both (a) & (b) |
| D. | neither (a) nor (b) |
| Answer» C. both (a) & (b) | |
| 633. |
Degree to which an instrument indicates the changes in measured variable without dynamic error is called its |
| A. | speed of response |
| B. | reproducibility |
| C. | fidielity |
| D. | static characteristics |
| Answer» D. static characteristics | |
| 634. |
The characteristic equation for the control system with a closed loop transfer function G1/1 + G2 is given by 1 + G2 = 0. The characteristic equation for the control system |
| A. | depends only upon the open loop transfer function. |
| B. | determines its stability. |
| C. | is the same for set point or load changes. |
| D. | all 'a', 'b' & 'c' |
| Answer» E. | |
| 635. |
What is the ratio of output amplitude to input amplitude for a sinusoidal forcing function in a first order system ? |
| A. | 1 |
| B. | >1 |
| C. | < 1 |
| D. | none of these |
| Answer» D. none of these | |
| 636. |
A mercury barometer measures the __________ pressure. |
| A. | atmospheric |
| B. | gauge |
| C. | vacuum |
| D. | absolute |
| Answer» B. gauge | |
| 637. |
Which of the following fluid flow measuring devices can measure the largest flow rate ? |
| A. | V-notch |
| B. | Rotameter |
| C. | Orificemeter |
| D. | Weir |
| Answer» E. | |
| 638. |
Mcleoid gauge is used to measure the |
| A. | point velocity |
| B. | flow rate |
| C. | vacuum |
| D. | pressure |
| Answer» D. pressure | |
| 639. |
A photo electric device in which the resistance of the metal is directly proportional to the light striking on it, is known as photo-conductive cell. Photoelectric transducers are used for the measurement of those parameters, which can be used to produce variation in |
| A. | light intensity |
| B. | current |
| C. | flux density |
| D. | voltage |
| Answer» B. current | |
| 640. |
Continuous measurement of specific gravity of a liquid is done by |
| A. | hydrometer |
| B. | contact-type electric indicators |
| C. | displacement meter |
| D. | both (a) and (c) |
| Answer» E. | |
| 641. |
Platinum resistance thermometer can be used upto antimony point which is __________ °C, and is the temperature of equilibrium between solid antimony & liquid antimony at normal atmospheric pressure.$ |
| A. | 961.93 |
| B. | 630.74 |
| C. | 1064.43 |
| D. | 1261.93 |
| Answer» C. 1064.43 | |
| 642. |
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. | |
| 643. |
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. | |
| 644. |
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. | |
| 645. |
Continuous measurement of moisture in paper is done by |
| A. | sling psychrometer. |
| B. | hair-hygrometer. |
| C. | weighing. |
| D. | high resistance Wheatstone's bridge circuit. |
| Answer» E. | |
| 646. |
Conversion formula for converting amplitude ratio (AR) into decibels is |
| A. | Decibel = 20 log10 (AR) |
| B. | Decibel = 20 loge (AR) |
| C. | Decibel = 20 log10 (AR)0.5 |
| D. | Decibel = 20 loge (AR)0.5 |
| Answer» B. Decibel = 20 loge (AR) | |
| 647. |
Polarisation of light forms the working principle of a |
| A. | polarimeter |
| B. | polarograph |
| C. | chromatograph |
| D. | spectrometer |
| Answer» B. polarograph | |
| 648. |
The deflection in diaphragm (which is used as pressure sensor in pneumatic and electronic instruments) is dependent on the metal thickness, its diameter (d) and shape & number of corrugations. Its deflection is proportional to |
| A. | d |
| B. | d2 |
| C. | d3 |
| D. | d4 |
| Answer» E. | |
| 649. |
Flow rate of a river is measured by a/an |
| A. | pitot tube |
| B. | vane meter |
| C. | kennison nozzle |
| D. | open weir |
| Answer» C. kennison nozzle | |
| 650. |
The open loop transfer function of a control system is . This represents |
| A. | a first order system. |
| B. | dead time system. |
| C. | a first order time lag. |
| D. | a second order system. |
| Answer» B. dead time system. | |