Process Control and Instrumentation

21. A non-linear system will have _________ steady state values.

  1. One
  2. More than one
  3. Two
  4. Three

Correct answer: (B)
More than one

22. 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

  1. Light intensity
  2. Current
  3. Flux density
  4. Voltage

Correct answer: (A)
Light intensity

23. A process is initially at steady state with its output y = 1 for an input u = 1. The input is suddenly changed to 2 at time t = 0. The output response is y(t) = 1 + 2t. The transfer function of the process is

  1. 2/s
  2. 1 + (2/S2)
  3. 1 + (2/s)
  4. (1/s) [1 + (2/s)]

Correct answer: (D)
(1/s) [1 + (2/s)]

24. A proportional controller with a gain of Kc is used to control a first order process. The offset will increase, if

  1. Kc is reduced
  2. Kc is increased
  3. Integral control action is introduced
  4. Derivative control action is introduced

Correct answer: (B)
Kc is increased

25. A pyranometer is an instrument used for measuring the

  1. Beam radiation
  2. Global radiation
  3. Bright sunshine period
  4. None of these

Correct answer: (B)
Global radiation

26. A pyrheliometer is an instrument used for measuring the

  1. Bright sunshine period
  2. Beam radiation
  3. Diffuse radiation
  4. None of these

Correct answer: (B)
Beam radiation

27. A simple pitot tube measures the

  1. Average velocity
  2. Maximum velocity
  3. Point velocity
  4. Static pressure

Correct answer: (D)
Static pressure

28. A sinusoidal variation in the input passing through a linear first order system

  1. Becomes more oscillatory (frequency increases)
  2. Becomes less oscillatory (frequency decreases)
  3. Gets amplified (magnitude increases)
  4. Gets attenuated (magnitude decreases)

Correct answer: (D)
Gets attenuated (magnitude decreases)

29. A stable system is the one

  1. For which the output response is bounded for all bounded input
  2. Which exhibits an unbounded response to a bounded input
  3. Which satisfies the conditions for a servo problem
  4. None of these

Correct answer: (A)
For which the output response is bounded for all bounded input

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

  1. Is a constant
  2. Grows exponentially with time
  3. Grows linearly with time
  4. Decays linearly with time

Correct answer: (C)
Grows linearly with time

Previous
Page 3 of 32
Next
Copyright © EngineeringMCQ.com