Process Control and Instrumentation MCQs

Question 1

In a feed-back control system G and H denote open loop and close loop transfer functions respectively. The output-input relationship is

Accepted Answer

$$\frac{{	ext{H}}}{{1 + {	ext{G}}}}$$

Answer

$$\frac{{	ext{G}}}{{1 + {	ext{H}}}}$$

Answer

$$\frac{{	ext{G}}}{{	ext{H}}}$$

Answer

$$\frac{{	ext{H}}}{{	ext{G}}}$$

Question 2

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

Accepted Answer

d 4

Answer

d

Answer

d 2

Answer

d 3

Question 3

What is the ratio of output amplitude to input amplitude for a sinusoidal forcing function in a first order system?

Accepted Answer

< 1

Answer

1

Answer

>1

Answer

None of these

Question 4

Bimetal strips are not used in

Accepted Answer

Thermocouples

Answer

Bimetallic thermometers

Answer

Thermostats

Answer

Relays for opening & closing of electrical circuits

Question 5

Emf generated in a thermocouple depends on the temperature

Accepted Answer

Difference between hot and cold junctions

Answer

Of cold junction only

Answer

Of hot junction only

Answer

Difference between cold junction and atmospheric temperature

Question 6

Thermodynamic celcius scale of temperature measurement is

Accepted Answer

Both B and C

Answer

Defined on the basis of melting point of ice and evaporation temperature of water vapor

Answer

Defined on the basis of melting point of ice and condensation temperature of water vapor

Answer

Having an interval of 100° between ice point to steam point

Question 7

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

Accepted Answer

Level of liquid

Answer

Heat content of the system

Answer

Liquid volume in the tank

Answer

Flow rate

Question 8

Which of the following is the dynamic characteristics of an instrument?

Accepted Answer

Fidelity

Answer

Reproducibility

Answer

Sensitivity

Answer

Dead zone

Question 9

Turbine flow meters are suitable for

Accepted Answer

Both B and C

Answer

Very limited flow ranges

Answer

Cryogenic flow measurements

Answer

Aerospace and in air borne applications