Automatic Control Systems MCQs : This section focuses on the "Automatic Control Systems". These Multiple Choice Questions (MCQs) should be practiced to improve the Automatic Control Systems skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.
Question 1
A lag compensator is essentially a
A. low pass filter
B. high pass filter
C. band pass filter
D. either (a) or (b)
Question 2
For the transport lag G(jω) = e-jωT, the magnitude is always equal to
A. 0
B. 1
C. 10
D. 0.5
Question 3
A stepper motor is
A. a two phase induction motor
B. is a kind of rotating amplifier
C. is an electromagnetic transducer used to convert an angular position of shaft into electrical signal
D. is an electromechanical device which actuates a train of step angular movements in response to a train of input pulses on one to one basis
Question 4
If a system is to follow arbitrary inputs accurately the bandwidth should be
A. large
B. small
C. very small
D. neither small nor large
Question 5
Assertion (A): Potentiometers can not be used as error detectors in position control systems.Reason (R): The resolution of a potentiometer places an upper limit on its accuracy
A. Both A and R are correct and R is correct explanation of A
B. Both A and R are correct but R is not correct explanation of A
C. A is correct but R is wrong
D. R is correct but A is wrong
Question 6
In a minimum phase system
A. all poles lie in the left half plane
B. all zeros lie in the left half plane
C. all poles lie in the right half plane
D. all except one pole or zero lie in the left half plane
Question 7
Mechanical impedance is the ratio of
A. rms force to rms velocity
B. rms force to rms displacement
C. rms velocity to rms displacement
D. none of the above
Question 8
When a unit step voltage drives a lag network the output
A. remains constant at unit step value
B. increases exponentially from zero to final value
C. decreases exponentially from 1 to 0
D. either (b) of (c) depending on values of R and C
Question 9
Stepper motors find applications in
A. X-Y plotters
B. numerically controlled machining equipment
C. printers
D. all of the above
Question 10
The log magnitude curve for a constant gain K is a
A. horizontal straight line
B. horizontal straight line of magnitude 20 log K decibels
C. an inclined line having slope K
D. an inclined line having slope -K
Question 11
From the noise point of view, bandwidth should
A. be large
B. not be too large
C. should be as large as possible
D. should be infinite
Question 12
The phase margin and damping ratio have no relation.
A. TRUE
B. FALSE
Question 13
Bellows converts
A. pressure difference into displacement
B. pressure difference into voltage
C. displacement into pressure difference
D. either (a) or (c)
Question 14
For type 2 system, the magnitude and phase angle of the term (jω)2 in the denominator, at ω = 0, are respectively
A. 0 and - 90°
B. 0 and + 90°
C. infinity and - 180°
D. infinity and + 180°
Question 15
Whether a linear system is stable or unstable that it
A. is a property of the system only
B. depends on the input function only
C. both (a) and (b)
D. either (a) or (b)
Question 16
Bode magnitude plot is drawn between
A. magnitude of network function and ω
B. dB magnitude and log ω
C. dB magnitude and ω
D. loge (magnitude) and log ω
Question 17
In an integral controller
A. the output is proportional to input
B. the rate of change of output is proportional to input
C. the output is proportional to rate of change of input
D. none of the above
Question 18
A system has its two poles on the negative real axis and one pair of poles lies on jω axis. The system is
A. stable
B. unstable
C. limitedly stable
D. either (a) or (c)