Pole- Zero effect on process response Objective Questions and Answers

1. Pressure error can be measured by which of the following?
a) Differential bellows and strain gauge
b) Selsyn
c) Strain gauge
d) Strain gauge and potentiometer
Answer: Differential bellows and strain gauge
2. Zeroes are defined as _______
a) Roots of the denominator of the closed loop transfer function
b) Roots of the numerator of the closed loop transfer function
c) Parts of the numerator
d) Parts of the denominator
Answer: Roots of the numerator of the closed loop transfer function
3. Addition of __________  increases the stability.
a) zero
b) one 
c) number
d) none of the mentioned
Answer: zero
4. _____________ is not a final control element.
a) Control valve
b) Potentiometer
c) Electro-pneumatic converter
d) Servomotor
Answer: Potentiometer
5. A control system is generally met with the time response specifications _____________
a) Steady state accuracy
b) Damping factor
c) Setting time
d) All of the mentioned
Answer: All of the mentioned
6. Steady state accuracy specified in terms of
a) Steady state error
b) Damping ratio
c) Natural frequency
d) All of the mentioned
Answer: Steady state error
7. Steady state accuracy is determined by suitable choice of____________
a) Steady error
b) Error constants
c) Damping
d) Transient error
Answer: Error constants
8. Which of the following can be measured by the use of a tacho-generator?
a) Acceleration
b) Speed
c) Speed and acceleration
d) Displacement
Answer: Speed
9. If rise time is also taken into consideration it should be ____________ to the settling time.
a) Inconsistent
b) Consistent
c) Perfect
d) Unique
Answer: Consistent
10. Assertion (A): The zeroes on the real axis near the origin are generally avoided in design.
Reason (R): In a sluggish system introduction of zeroes can improve the transient response
a) Both A and R are true and R is correct explanation of A
b) Both A and R are true but R is not correct explanation of A
c) A is true but R is false
d) A is false but R is true
Answer: Both A and R are true but R is not correct explanation of A
11. Assertion (A): Lead compensation is used to improve the system’s stability
Reason (R): Lead compensation achieves the desired result through the merits of its phase lead contribution.
a) Both assertion and reason are true and R is correct explanation of A
b) Both A and R true but R is not correct explanation of A
c) A is true but R is false
d) A is False but R is true
Answer: Both assertion and reason are true and R is correct explanation of A
12. Damping factor specifies _________
a) Peak overshot to step input.
b) Steady state error
c) Damping ratio
d) Natural frequency
Answer: Peak overshot to step input.
13. Which of the following is the definition of proportional band of a controller?
a) The range of air output as measured variable varies from maximum to minimum
b) The range of measured variables from set value
c) The range of measured variables through which the air output changes from maximum to minimum
d) All of the mentioned
Answer: The range of measured variables through which the air output changes from maximum to minimum
14. Assertion (A): A PI controller increases the order of the system by units but decreases the steady state error.
Reason (R): A PI controller introduces a pole at either the origin or at a desired points on the negative real axis.
a) Both assertion and reason are true and R is correct explanation of A
b) Both A and R true but R is not correct explanation of A
c) A is true but R is false
d) A is False but R is true
Answer: Both assertion and reason are true and R is correct explanation of A
15. Assertion (A): Feedback compensation is preferred to series compensation.
Reason (R): No amplification is required as the energy flows from higher to lower levels.
a) Both assertion and reason are true and R is correct explanation of A
b) Both A and R true but R is not correct explanation of A
c) A is true but R is false
d) A is False but R is true
Answer: Both assertion and reason are true and R is correct explanation of A
16. A plant is controlled by a proportional controller, if time delay element is introduced in the loop its _________
a) Phase margin remains the same
b) Phase margin increases
c) Phase margin decreases
d) Gain margin increases
Answer: Phase margin decreases
17. Assertion (A): A derivative controller produces a control action for constant error only.
Reason (R): The PD controller increases the damping and reduces the peak overshoot.
a) Both assertion and reason are true and R is correct explanation of A
b) Both A and R true but R is not correct explanation of A
c) A is true but R is false
d) A is False but R is true
Answer: A is False but R is true
18. If number of poles are greater than number of zeroes then the system is known as _________
a) Stable system
b) Unstable system
c) Minimum phase system
d) Non-minimum phase system
Answer: Minimum phase system
19. In pneumatic control systems the control valve used as final control element converts
a) Pressure signal to electric signal
b) Pressure signal to position change
c) Electric signal to pressure signal
d) Position change to pressure signal
Answer: Pressure signal to position change
20. Addition of zero increases the stability.
a) True
b) False
Answer: True
21. Potentiometer is not a final control element.
a) True
b) False
Answer: True
22. As zero moves sufficiently left from the origin the effect of zero becomes less pronounced.
a) True
b) False
Answer: True
23. Zeroes are defined as Roots of the denominator of the closed loop transfer function
a) True
b) False
Answer: False
24. Electro-pneumatic converter is not a final control element.
a) True
b) False
Answer: False
25. A PI controller increases the order of the system by units but decreases the steady state error.
a) True
b) False
Answer: True