Process Control and Instrumentation MCQs

Question 1

A negative gain margin expressed in decibels means a/an __________ system.

Accepted Answer

Unstable

Answer

Stable

Answer

Critically damped

Answer

None of these

Question 2

Range of hydrogen gas constant volume themometer is __________ °C.

Accepted Answer

0 to 100

Answer

-10 to 20

Answer

100 - 500

Answer

400 - 1000

Question 3

Flow rate measurement of hostile acids and alkalis can be most suitably done by a/an

Accepted Answer

Magnetic flow meter

Answer

Venturimeter

Answer

Orificemeter

Answer

Hot wire anemometer

Question 4

A stable system is the one

Accepted Answer

For which the output response is bounded for all bounded input

Answer

Which exhibits an unbounded response to a bounded input

Answer

Which satisfies the conditions for a servo problem

Answer

None of these

Question 5

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

Accepted Answer

Rotameter

Answer

Flow nozzle

Answer

Orificemeter

Answer

Venturimeter

Question 6

Phase lag of the sinusoidal response of a first order system is

Accepted Answer

90°

Answer

120°

Answer

30°

Answer

180°

Question 7

Liquid flow rate in an open channel can not be measured by a/an

Accepted Answer

Orifice meter

Answer

Cipolletti weir

Answer

Rectangular weir

Answer

V-notch

Question 8

A magnetic flowmeter is

Accepted Answer

All of the above

Answer

Based on the principle of Faraday's law

Answer

Capable of measuring the flow rate of slurries and electrolytes

Answer

Based on the linear relationship between the fluid flow rate and the induced voltage

Question 9

The characteristic equation for the control system with a closed loop transfer function $$\frac{{{{	ext{G}}_1}}}{{1 + {{	ext{G}}_2}}}$$ is given by $$1 + {{	ext{G}}_2} = 0$$ The characteristic equation for the control system

Accepted Answer

All of the above

Answer

Depends only upon the open loop transfer function

Answer

Determines its stability

Answer

Is the same for set point or load changes