Process Control and Instrumentation MCQs

Question 1

Which of the following is a 'contact' pyrometer?

Accepted Answer

Resistance pyrometer

Answer

Optical pyrometer

Answer

Radiation pyrometer

Answer

Infra red pyrometer

Question 2

A non-linear chemical system is exemplified by a/an

Accepted Answer

Non-isothermal CSTR

Answer

Isothermal CSTR

Answer

Mixer

Answer

None of these

Question 3

Humidity of air can be determined by a

Accepted Answer

Sling psychrometer

Answer

Chromatograph

Answer

Mass spectrometer

Answer

Polarimeter

Question 4

Which of the following relates the absorption & evolution of heat at the junctions of a thermocouple to the current flow in the circuit?

Accepted Answer

Peltier effect

Answer

Seebeck effect

Answer

Joule heating effect

Answer

Thomson effect

Question 5

Continuous measurement of moisture content of paper in paper industry is done by measuring the

Accepted Answer

Electrical resistance through the paper

Answer

Thermal conductivity through the paper

Answer

Magnetic susceptibility

Answer

None of these

Question 6

In a single tank system, the transfer function of __________ to inlet flow rate is $$\frac{1}{{{	ext{TS}} + 1}}.$$

Accepted Answer

Outlet flow rate

Answer

Level

Answer

Both A & B

Answer

Neither A nor B

Question 7

With increase in temperature, the electrical conductivity of the platinum used in the resistance thermometer

Accepted Answer

Decreases

Answer

Increases

Answer

Remains constant

Answer

Increases exponentially

Question 8

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

Accepted Answer

180°

Answer

0°

Answer

45°

Answer

90°

Question 9

Thermal wells are used in the temperature measurement to

Accepted Answer

Guard against corrosive and oxidising action on thermocouple materials

Answer

Reduce measuring lag

Answer

Increase the fidelity

Answer

Increase the sensitivity