Engineering > Electrical Engineering

AUTOMATIC CONTROL SYSTEMS MCQs

Total Questions : 50

Page 1 of 3 pages
Question 1. In control systems the output of sensor usually, is
  1.     Analog electrical signal
  2.     Digital electrical signal
  3.     Mechanical signal
  4.     Analog or digital electrical signal
Answer: Option D
Question 2. In root locus analysis the breakaway and break in points
  1.     lie on the real axis
  2.     Either lie on the real axis or occur in complex conjugate pairs
  3.     Always occur in complex conjugate pairs
  4.     None of the above
Answer: Option B
Question 3. If any term in the first column of a routh array becomes zero, then
  1.     Routh criterion cannot be used to determine stability
  2.     Routh criterion can be used by substituting a small positive number for zero and completing the array
  3.     Routh criterion can be used by substituting a big positive number for zero and completing the array
  4.     Routh criterion can be used by substituting a small negative number for zero and complet-ing the array
Answer: Option B
Question 4. Integral control action
  1.     Removes offset
  2.     May lead to oscillatory response
  3.     Both (a) and (b)
  4.     Neither (a) nor (b)
Answer: Option C
Question 5. For type 1 system the velocity lag error is
  1.     Inversely proportional to bandwidth of system
  2.     Directly proportional to gain constant
  3.     Inversely proportional to gain constant
  4.     Independent of gain constant
Answer: Option C
Question 6. Lag compensation permits a high gain at low frequencies.
  1.     True
  2.     False
  3.     Always occur in complex conjugate pairs
  4.     None of the above
Answer: Option A
Question 7. A lag compensator
  1.     Speeds up the transient response of the system
  2.     Improves steady state behavior of the system
  3.     Improves steady state behavior and speeds up the transient response of the system
  4.     Improves steady state behavior and preserves the transient response of the system
Answer: Option D
Question 8. A lead compensator
  1.     Speeds up the transient response
  2.     Increases the stability margin
  3.     Increases the stability margin and speeds up the transient-response.
  4.     None of the above
Answer: Option C
Question 9. Robotic manipulator arms mostly use
  1.     Hydraulic actuator
  2.     Pneumatic actuator
  3.     Electric motor actuator
  4.     None of the above
Answer: Option C
Question 10. In bode plots the frequency at which two asymptotes meet is called corner frequency.
  1.     True
  2.     False
  3.     Motor friction and load
  4.     Field resistance
Answer: Option A
Question 11. Gain margin and phase margin can be determined from bode plots as well as nyquist plot.
  1.     True
  2.     False
  3.     Both (a) and (b)
  4.     Neither (a) nor (b)
Answer: Option A
Question 12. For a stable system having two or more gain crossover frequencies the phase margin is measured at the highest crossover frequency.
  1.     True
  2.     False
Answer: Option A
Question 13. Which of the following can be used as a rotating amplifier in a control system?1. amplidyne2. separately excited dc generator3. synchro4. self excited dc generator
  1.     3 and 4
  2.     1 and 2
  3.     1, 2 and 3
  4.     All
Answer: Option B
Question 14. The sensor generally used in incremental optical encoder is
  1.     LED
  2.     LCD
  3.     Photodiode
  4.     Either (a) or (b)
Answer: Option C
Question 15. The poles with greater displacement from the real axis correspond to
  1.     Higher frequencies of oscillations
  2.     Stable response
  3.     Lower frequencies of oscillations
  4.     Unbounded output
Answer: Option A
Question 16. In force current analogue, mechanical mobility is analogous to
  1.     Impedance Z
  2.     Admittance Y
  3.     Reactance X
  4.     Conductance G
Answer: Option A
Question 17. Nichols chart consists of
  1.     Constant magnitude loci
  2.     Constant phase angle loci
  3.     Magnitude and phase angle loci in log-magnitude versus phase diagram
  4.     None of the above
Answer: Option C
Question 18. Magnetic amplifier is used for
  1.     Voltage amplification
  2.     Power amplification
  3.     Current amplification
  4.     Frequency amplification
Answer: Option B
Question 19. Which control action can never be used alone?
  1.     Proportional
  2.     Derivative
  3.     Integral
  4.     Both (b) and (c)
Answer: Option B
Question 20. In a simple on-off controller with differential gap, the magnitude of differential gap determines
  1.     The level of accuracy
  2.     The life of controller
  3.     Both (a) and (b)
  4.     Neither (a) nor (b)
Answer: Option C