Control Systems Questions and Answers – The Approximation of Higher-Order Systems by Lower-Order

This set of Control Systems Multiple Choice Questions & Answers (MCQs) focuses on “The Approximation of Higher-Order Systems by Lower-Order”.

1. The output of a feedback control system must be a function of
a) Reference and output
b) Reference and input
c) Input and feedback signal
d) Output and feedback signal
View Answer

Answer: a
Explanation: The output from the feedback control system must be a function of the reference input and output.

2. A control system with excessive noise, is likely to suffer from?
a) Saturation in amplifying stages
b) Loss of gain
c) Vibrations
d) Oscillations
View Answer

Answer: a
Explanation: A control system with excessive noise suffers from the saturation due to multiple inputs and outputs present and high gain of the system.

3. Zero initial condition for a system means?
a) Input reference signal is zero
b) Zero stored energy
c) Initial movement of moving parts
d) System is at rest and no energy is stored in any of its components
View Answer

Answer: d
Explanation: Zero initial condition for a system means the system is at rest and no energy is stored in any of its components.
advertisement
advertisement

4. Transfer function of a system is used to calculate which of the following?
a) The order of the system
b) The time constant
c) The output for any given input
d) The steady state gain
View Answer

Answer: c
Explanation: The output of any given system can be calculated by the transfer function of the system and this is the ratio of Laplace output to the Laplace input considering zero initial conditions.

5. The band width, in a feedback amplifier.
a) Remains unaffected
b) Decreases by the same amount as the gain increase
c) Increases by the same amount as the gain decrease
d) Decreases by the same amount as the gain decrease
View Answer

Answer: c
Explanation: The bandwidth of closed loop systems Increases by the same amount as the gain decreases hence increasing the noise due to increased bandwidth.

6. On which of the following factors does the sensitivity of a closed loop system to gain changes and load disturbances depend?
a) Frequency
b) Loop gain
c) Forward gain
d) All of the mentioned
View Answer

Answer: d
Explanation: The sensitivity depends upon the frequency, loop gain and forward gain of the closed loop control system.

7. The transient response, with feedback system,
a) Rises slowly
b) Rises quickly
c) Decays slowly
d) Decays quickly
View Answer

Answer: d
Explanation: The transient response of the system is improved with the help of the feedback and hence the transient response decays quickly.
advertisement

8. The second derivative input signals modify which of the following?
a) The time constant of the system
b) Damping of the system
c) The gain of the system
d) The time constant and suppress the oscillations
View Answer

Answer: d
Explanation: The second derivative of the input signal modify the time constant and suppress the oscillations.

9. Which of the following statements is correct for any closed loop system?
a) All the co-efficient can have zero value
b) All the co-efficient are always non-zero
c) Only one of the static error co-efficient has a finite non-zero value
d) Only two of the static error co-efficient has a finite non-zero value
View Answer

Answer: c
Explanation: Closed loop system has one of the static error constants for any input that can be position, velocity or acceleration error constant which has finite non-zero values.
advertisement

10. Which of the following statements is correct for a system with gain margin close to unity or a phase margin close to zero?
a) The system is relatively stable
b) The system is highly stable
c) The system is highly oscillatory
d) The system is stable
View Answer

Answer: c
Explanation: The system is highly oscillatory or unstable as the value of phase margin must be finite for the stable system.

Sanfoundry Global Education & Learning Series – Control Systems.
To practice all areas of Control Systems, here is complete set of 1000+ Multiple Choice Questions and Answers.

If you find a mistake in question / option / answer, kindly take a screenshot and email to [email protected]

advertisement
advertisement
Subscribe to our Newsletters (Subject-wise). Participate in the Sanfoundry Certification contest to get free Certificate of Merit. Join our social networks below and stay updated with latest contests, videos, internships and jobs!

Youtube | Telegram | LinkedIn | Instagram | Facebook | Twitter | Pinterest
Manish Bhojasia - Founder & CTO at Sanfoundry
Manish Bhojasia, a technology veteran with 20+ years @ Cisco & Wipro, is Founder and CTO at Sanfoundry. He lives in Bangalore, and focuses on development of Linux Kernel, SAN Technologies, Advanced C, Data Structures & Alogrithms. Stay connected with him at LinkedIn.

Subscribe to his free Masterclasses at Youtube & discussions at Telegram SanfoundryClasses.