Explore topic-wise MCQs in Control Systems.

This section includes 43 Mcqs, each offering curated multiple-choice questions to sharpen your Control Systems knowledge and support exam preparation. Choose a topic below to get started.

1.

" Consider the following statements for the pneumatic and hydraulic systems:1. The normal operating pressure of pneumatic control is very much higher than that of hydraulic control.2. In, pneumatic control external leakage is permissible to a certain extent, but there should no leakage in a hydraulic control.Which of the statements given above is/are correct?"

A. " 1 only"
B. " 2 only"
C. " Both 1 and 2"
D. " Neither 1 and 2"
Answer» D. " Neither 1 and 2"
2.

" The impulse response of a linear LTI system is given as g (t) = e(-t)The transfer function of the system is equal to:"

A. " 1/s"
B. " 1/s(s+1)"
C. " 1/(s+1)"
D. " s/(s+1)"
Answer» D. " s/(s+1)"
3.

" The transfer function of any stable system which has no zeros or poles in the right half of the s-plane is said to be:"

A. " Minimum phase transfer function"
B. " Non-minimum phase transfer function"
C. " Minimum phase frequency response function"
D. " Minimum gain transfer function"
Answer» B. " Non-minimum phase transfer function"
4.

" A differentiator is usually not a part of a control system because it"

A. " Reduces damping"
B. " Reduces the gain margin"
C. " Increases input noise"
D. " Increases error"
Answer» D. " Increases error"
5.

" In an open loop control system"

A. " Output is independent of control input"
B. " Output is dependent on control input"
C. " Only system parameters have effect on the control output"
D. " None of the mentioned"
Answer» B. " Output is dependent on control input"
6.

" ______________ are the techniques for converting general state models into canonical one."

A. Observable
B. Controllable
C. Diagoanlization
D. Cannonical
Answer» D. Cannonical
7.

" ____________directly converts temperature into voltage."

A. " Thermocouple"
B. " Potentiometer"
C. " Gear train"
D. " LVDT"
Answer» B. " Potentiometer"
8.

" The tacho meter has sensitivity of 5V/1000rpm. The gain constant of the tacho meter is:"

A. " 0.48V/rad/sec"
B. " 0.048V/rad/sec"
C. " 4.8V/rad/sec"
D. " 48V/rad/sec"
Answer» C. " 4.8V/rad/sec"
9.

" If the initial conditions are inherently zero, what does it physically mean?"

A. " The system is at rest but stores energy"
B. " The system is working but does not store energy"
C. " The system is at rests or no energy is stored in any of its parts"
D. " The system is working with zero reference input"
Answer» D. " The system is working with zero reference input"
10.

" Consider the following servomotors:1. AC-two phase servomotor2. DC servomotor3. Hydraulic servomotor4. Pneumatic servomotorThe correct sequence of these servomotor in increasing order of power handling capacity is:"

A. " 2,4,3,1"
B. " 4,2,3,1"
C. " 2,4,1,3"
D. " 4,2,1,3"
Answer» D. " 4,2,1,3"
11.

" Open loop transfer function of a system having one zero with a positive real value is called."

A. " Zero phase function"
B. " Negative phase function"
C. " Positive phase function"
D. " Non-minimum phase function"
Answer» E.
12.

" A tachometer is used as an inner loop in a position control servo-system. What is the effect of feedback on the gain of the sub-loop incorporating tachometer and in the effective time constant of the system?"

A. " Both are reduced"
B. " Gain is reduced but the time constant is increased"
C. " Gain is increased but the time constant is reduced"
D. " Both are increased"
Answer» B. " Gain is reduced but the time constant is increased"
13.

" If the gain of the critical damped system is increased it will behave as"

A. " Oscillatory"
B. " Critically damped"
C. " Overdamped"
D. " Underdamped"
Answer» E.
14.

" Error detector:"

A. " Armature controlled FHP DC motor"
B. " A pair of synchronous transmitter and control transformer"
C. " Tach generator"
D. " Amplidyne"
Answer» B. " A pair of synchronous transmitter and control transformer"
15.

" In a closed loop for which the output is the speed of the motor, the output rate control can be used to:"

A. " Limit the speed of the motor"
B. " Limit the torque output of the motor"
C. " Reduce the damping of the system"
D. " Limit the acceleration of the motor"
Answer» B. " Limit the torque output of the motor"
16.

" When human being tries to approach an object, his brain acts as,"

A. " An error measuring device"
B. " A controller"
C. " An actuator"
D. " An amplifier"
Answer» C. " An actuator"
17.

" Consider the function F (s)= 5/s(s2+3s+2), the initial value of f(t) is:"

A. " 5"
B. " 5/2"
C. " 5/3"
D. " 0"
Answer» E.
18.

" Assertion (A): The stator winding of a control transformer has higher impedance per phaseReason (R): The rotor of control transformer is cylindrical in shape."

A. " Both A and R are true and R is correct explanation of A"
B. " Both A and R are true and R is not correct Explanation of A"
C. " A is True and R is false"
D. " A is False and R is true"
Answer» C. " A is True and R is false"
19.

" The transfer function of a LTI system is given as 1/(s+1). What is the steady-state value of the unit-impulse response?"

A. " 0"
B. " 1"
C. " 2"
D. " Infinite"
Answer» B. " 1"
20.

" The values of the characteristic equation is given by:"

A. " Eigen values"
B. " State matrix"
C. " Eigen vector"
D. " None of the mentioned"
Answer» B. " State matrix"
21.

" Consider the following statements relating to synchro's:1. The rotor of the control transformer is either disc shaped2. The rotor of the transmitter is so constructed as to have a low magnetic reluctance3. Transmitter and control transformer pair is used as an error detectorWhich of these statements are correct?"

A. " 1,2 and3"
B. " 1 and 2"
C. " 2 and3"
D. " 1 and 3"
Answer» D. " 1 and 3"
22.

" The matrix constructed by placing the Eigen vectors together is diagonalizing matrix."

A. " True"
B. " False"
Answer» B. " False"
23.

" An electric motor is developing 10KW at a speed of 900rpm. The torque available at the shaft is:"

A. " 106 N-m"
B. " 66 N-m"
C. " 1600 N-m"
D. " 90 N-m"
Answer» B. " 66 N-m"
24.

The transfer function for the state representation of the continuous time LTI system:dq(t)/dt=Aq(t)+Bx(t)Y(t)=Cq(t)+Dx(t)is given by:

A. C(sI-A)-1B+D
B. B(sI-A)-1B+D
C. C(sI-A)-1B+A
D. D(sI-A)-1B+C
Answer» B. B(sI-A)-1B+D
25.

" Which of the following can be used as a tacho generator in control systems?"

A. " Microsyn"
B. " DC servomotor"
C. " AC servomotor"
D. " Magnetic Amplifier"
Answer» D. " Magnetic Amplifier"
26.

" In case of DC servomotor the back-emf is equivalent to an 'electric friction' which tends to :"

A. " Improve stability of the motor"
B. " Slowly decrease stability of the motor"
C. " Vary rapidly decrease stability of the motor"
D. " Have no effect on stability"
Answer» B. " Slowly decrease stability of the motor"
27.

" Assertion (A): Many of the linear control system transfer function do not have poles or zeroes in the right half s-plane.Reason (R): These are called minimum phase transfer function."

A. " Both A and R are true and R is correct explanation of A"
B. " Both A and R are true and R is not correct Explanation of A"
C. " A is True and R is false"
D. " A is False and R is true"
Answer» B. " Both A and R are true and R is not correct Explanation of A"
28.

" Assertion (A): In a shunt regulator, the control element is connected in shunt with the load to achieve constant output voltage.Reason (R): The impedance of the control element varies to keep the total current flowing through the load and the control element constant."

A. " Both A and R are true and R is correct explanation of A"
B. " Both A and R are true and R is not correct Explanation of A"
C. " A is True and R is false"
D. " A is False and R is true"
Answer» D. " A is False and R is true"
29.

" Which of the following is an electromechanical device ?"

A. " Induction relay"
B. " Thermocouple"
C. " LVDT"
D. " Any of the mentioned"
Answer» D. " Any of the mentioned"
30.

" Assertion (A): In the error detector configuration using a synchro transmitter and synchro control transformer, the latter is connected to the error amplifier.Reason (R): Synchro control transformer has almost a uniform reluctance path between the rotor and the stator."

A. " Both A and R are true and R is correct explanation of A"
B. " Both A and R are true and R is not correct Explanation of A"
C. " A is True and R is false"
D. " A is False and R is true"
Answer» D. " A is False and R is true"
31.

" The diagonalizing matrix is also known as:"

A. " Eigen matrix"
B. " Modal matrix"
C. " Constant matrix"
D. " State matrix"
Answer» C. " Constant matrix"
32.

" State model is generally not suitable for measuring:"

A. " Investigation of system properties"
B. " Evaluation of time response"
C. " Real variables"
D. " Both a and b"
Answer» E.
33.

" State space analysis is applicable for non-linear systems and for multiple input and output systems."

A. " True"
B. " False"
Answer» B. " False"
34.

" Which of the following can be measured by LVDT?"

A. " Displacement"
B. " Velocity"
C. " Acceleration"
D. " All of the mentioned"
Answer» E.
35.

" The closed loop transfer function of a unity negative feedback system is 100/(s2+8s+100). Its open loop transfer function is:"

A. " 100/s+8"
B. " 1/s2+8s"
C. " 100/s2-8s"
D. " 100/s2+8s"
Answer» E.
36.

" For two-phase AC servomotor, if the rotor's resistance and reactance are respectively R and X, its length and diameter are respectively L and D then,"

A. " X/R and L/D are both small"
B. " X/R is large but L/D is small"
C. " X/R is small but L/D is large"
D. " X/R and L/D are both large"
Answer» D. " X/R and L/D are both large"
37.

" In a control system integral error compensation _______ steady state error"

A. " Increases"
B. " Minimizes"
C. " Does not have any effect on"
D. " All of the mentioned"
Answer» C. " Does not have any effect on"
38.

" Servomotor:"

A. " Armature controlled FHP DC motor"
B. " A pair of synchronous transmitter and control transformer"
C. " Tach generator"
D. " Amplidyne"
Answer» C. " Tach generator"
39.

" The transfer function technique is considered as inadequate under which of the following conditions?"

A. " Systems having complexities and non-linearity's"
B. " Systems having stability problems"
C. " Systems having multiple input disturbances"
D. " All of the mentioned"
Answer» E.
40.

" Assertion (A): Transfer function approach has limitation that it reveals only the system output for a input and provides no information regarding the internal state of the system.Reason (R): There may be situations where the output of a system is stable and yet some of the system elements may have a tendency to exceed their specified ratings."

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» B. " Both A and R are true but R is not correct explanation of A"
41.

" In servo-system, the device used for derivative feedback is known as:"

A. " Synchro"
B. " Servomotor"
C. " Potentiometer"
D. " Tacho generator"
Answer» E.
42.

" State models presented employed:"

A. " Physical variables"
B. " Phase variables"
C. " Canonical variables"
D. " All of the mentioned"
Answer» E.
43.

" Amplifier:"

A. " Armature controlled FHP DC motor"
B. " A pair of synchronous transmitter and control transformer"
C. " Tach generator"
D. " Amplidyne"
Answer» E.