Process Control & Instrumentation Objective Questions – Set 4

Silver point temperature is __________ °C.

A typical example of a physical system with under damped characteristic is a

Which of the following thermocouples is capable of measuring a temperature of -50°C?

Routh test

An aneroid barometer measures the __________ pressure.

Bode diagram are generated from output response of the system subjected to which of the following input?

__________ stability method uses open loop transfer function.

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

Stability of a control system containing a transportation lag can be best analysed by

What is the normal percentage of rhodium in platinum + rhodium element used in the thermocouple ?

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 ?

Very low pressure is expressed in microns(μ), which is equal to __________ mm of Hg coloumn (absolute) at 0°C.

Which of the following filled system expansion thermometers has the lowest positive temperature measurement capability ?

Helium gas constant volume thermometer is suitable for the measurement of a temperature of __________ °C.

Mercury thermometer can be used to measure the temperature upto __________ °C.

Hot wire anemometer is used for the measurement of

Which of the following thermocouples is the most suitable for measuring a temperature of about 1600°C in an oxidizing atmosphere ?

Cascade control means

Dilatometer is used to measure

Thermal wells are used in the temperature measurement to

The offset introduced by proportional controller with gain K^c in response of first order system can be reduced by

Liquid column manometers are used for measuring the pressure __________ kgf/cm² .

Stabilising time for the controllers is the time required for the response to reach __________ percent of its ultimate value.

A first order system with a time constant of 1 min is subjected to frequency response analysis. At an input frequency of 1 radian/min, the phase shift is

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

In an exothermic chemical reactor, the manipulated variable is the flow rate of

Composition of alloys can be determined by

Working principle of mercury in glass thermometer is based on the __________ of mercury with increase in temperature.

pH meter has

Working principle of mercury in glass thermometer is based on volumetric expansion of mercury with increase in temperature. Which of the following undergoes minimum volumetric expansion for a given temperature change ?

Emf generated in a thermocouple depends on the temperature

A system with a double pole at the origin is unstable since the corresponding term in the time domain

Response of a linear control system for a change in set point is called

Which of the following does not figure in the list of seven substances selected for international temperature scale ?

Optical activity of a solution can be determined using a

When a bare thermocouple is covered by a protective sheath, the response becomes

A constant volume gas thermometer employing __________ is used to measure sub-zero (i.e., < 0° C) temperature.

The term analogous to voltage in a single tank system is the

Temperature measurement by optical pyrometer is done above __________ point, which is 1063°C.

Thermal conductivity based continuous flue gas analyser makes use of varying thermal conductivity of the constituents of flue gases. Which of the following constituents of flue gases has the maximum thermal conductivity ?

In a shell and tube heat exchanger, the outlet temperature of heating/cooling fluid is the __________ variable.

Meleoid gauge measures the __________ pressure.

A pyranometer is an instrument used for measuring the

Radiation thermometer can not measure the temperature

Mass spectrometer is used for the composition analysis of

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

All the thermocouples used for temperature measurement use dissimilar metal

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

Bourdon gauges are used for measuring pressure (kg/cm² )

Which of the following is not a differential pressure flow meter ?