Control Systems Test Questions Set 1

1)   Which terminology deals with the excitation or stimulus applied to the system from an external source for the generation of an output?

a. Input signal
b. Output signal
c. Error signal
d. Feedback signal
Answer  Explanation  Related Ques

ANSWER: Input signal

Explanation:
No explanation is available for this question!


2)   Which among the following is not an advantage of an open loop system?

a. Simplicity in construction & design
b. Easy maintenance
c. Rare problems of stability
d. Requirement of system recalibration from time to time
Answer  Explanation  Related Ques

ANSWER: Requirement of system recalibration from time to time

Explanation:
No explanation is available for this question!


3)   Which notation represents the feedback path in closed loop system representation?

a. b(t)
b. c(t)
c. e(t)
d. r(t)
Answer  Explanation  Related Ques

ANSWER: b(t)

Explanation:
No explanation is available for this question!


4)   Which among the following represents an illustration of closed loop system?

a. Automatic washing machine
b. Automatic electric iron
c. Bread toaster
d. Electric hand drier
Answer  Explanation  Related Ques

ANSWER: Automatic electric iron

Explanation:
No explanation is available for this question!


5)   How is an output represented in the control systems?

a. r(t)
b. c(t)
c. x(t)
d. y(t)
Answer  Explanation  Related Ques

ANSWER: c(t)

Explanation:
No explanation is available for this question!


6)   The output is said to be zero state response because ______conditions are made equal to zero.

a. Initial
b. Final
c. Steady state
d. Impulse response
Answer  Explanation  Related Ques

ANSWER: Initial

Explanation:
No explanation is available for this question!


7)   Basically, poles of transfer function are the laplace transform variable values which causes the transfer function to become ___________

a. Zero
b. Unity
c. Infinite
d. Average value
Answer  Explanation  Related Ques

ANSWER: Infinite

Explanation:
No explanation is available for this question!


8)   By equating the denominator of transfer function to zero, which among the following will be obtained?

a. Poles
b. Zeros
c. Both a and b
d. None of the above
Answer  Explanation  Related Ques

ANSWER: Poles

Explanation:
No explanation is available for this question!


9)   The output signal is fed back at the input side from the _________point

a. Summing
b. Differential
c. Take-off
d. All of the above
Answer  Explanation  Related Ques

ANSWER: Take-off

Explanation:
No explanation is available for this question!


10)   In a parallel combination, the direction of flow of signals through blocks in parallel must resemble to the main _______

a. Forward
b. Feedback
c. Opposite
d. Diagonal
Answer  Explanation  Related Ques

ANSWER: Forward

Explanation:
No explanation is available for this question!


11)   While shifting a take-off point after the summing point, which among the following should be added?

a. Summing point in series with take-off point
b. Summing point in parallel with take-off point
c. Block of reciprocal transfer function
d. Block of inverse transfer function
Answer  Explanation  Related Ques

ANSWER: Summing point in series with take-off point

Explanation:
No explanation is available for this question!


12)   Consider the assertions related to block diagram. Which among them represents the precise condition?

A. Block diagram is used for analysis & design of control system.
B. Block diagram also provides the information regarding the physical construction of the system.


a. A is true, B is false
b. A is false, B is true
c. Both A & B are true
d. Both A & B are false
Answer  Explanation  Related Ques

ANSWER: A is true, B is false

Explanation:
No explanation is available for this question!


13)   In a signal flow graph, nodes are represented by small _____

a. Circles
b. Squares
c. Arrows
d. Pointers
Answer  Explanation  Related Ques

ANSWER: Circles

Explanation:
No explanation is available for this question!


14)   According to signal flow graph, which among the following represents the relationship between nodes by drawing a line between them?

a. Branch
b. Self-loop
c. Semi-node
d. Mesh
Answer  Explanation  Related Ques

ANSWER: Branch

Explanation:
No explanation is available for this question!


15)   Which type of node comprises incoming as well as outgoing branches?

a. Source node
b. Sink node
c. Chain node
d. Main node
Answer  Explanation  Related Ques

ANSWER: Chain node

Explanation:
No explanation is available for this question!


16)   Where are the dummy nodes added in the branch with unity gain?

a. At input & output nodes
b. Between chain nodes
c. Both a and b
d. None of the above
Answer  Explanation  Related Ques

ANSWER: At input & output nodes

Explanation:
No explanation is available for this question!


17)   According to the property of impulse test signal, what is the value of an impulse at t = 0?

a. Zero
b. Unity
c. Infinite
d. Unpredictable
Answer  Explanation  Related Ques

ANSWER: Infinite

Explanation:
No explanation is available for this question!


18)   What is the value of parabolic input in Laplace domain?

a. 1
b. A/s
c. A/s2
d. A/s3
Answer  Explanation  Related Ques

ANSWER: A/s3

Explanation:
No explanation is available for this question!


19)   Which among the following is/are an/the illustration/s of a sinusoidal input?

a. Setting the temperature of an air conditioner
b. Input given to an elevator
c. Checking the quality of speakers of music system
d. All of the above
Answer  Explanation  Related Ques

ANSWER: Checking the quality of speakers of music system

Explanation:
No explanation is available for this question!


20)   If a system is subjected to step input, which type of static error coefficient performs the function of controlling steady state error?

a. Position
b. Velocity
c. Acceleration
d. Retardation
Answer  Explanation  Related Ques

ANSWER: Position

Explanation:
No explanation is available for this question!


21)   On the basis of an output response, into how many parts can the s-plane be divided?

a. 2
b. 3
c. 4
d. 6
Answer  Explanation  Related Ques

ANSWER: 3

Explanation:
No explanation is available for this question!


22)   If the complex conjugate poles are located at RHP, what would be the nature of corresponding impulse response?

a. Exponential
b. Damping oscillations
c. Increasing amplifier
d. Constant amplitude oscillations
Answer  Explanation  Related Ques

ANSWER: Increasing amplifier

Explanation:
No explanation is available for this question!


23)   Which among the following are solely responsible in determining the speed of response of control system?

a. Poles
b. Zeros
c. Speed of input
d. All of the above
Answer  Explanation  Related Ques

ANSWER: Poles

Explanation:
No explanation is available for this question!


24)   If a pole is located at s = -5 in left-hand plane (LHP), how will it be represented in Laplace domain?

a. 1/ s + 5
b. 1/ s - 5
c. s/ s + 5
d. s/ s - 5
Answer  Explanation  Related Ques

ANSWER: 1/ s + 5

Explanation:
No explanation is available for this question!


25)   In second order system, which among the following remains independent of gain (k)?

a. Open loop poles
b. Closed loop poles
c. Both a and b
d. None of the above
Answer  Explanation  Related Ques

ANSWER: Open loop poles

Explanation:
No explanation is available for this question!


26)   Root locus specifies the movement of closed loop poles especially when the gain of system  ________

a. Remains constant
b. Exhibit variations
c. Gives zero feedback
d. Gives infinite poles
Answer  Explanation  Related Ques

ANSWER: Exhibit variations

Explanation:
No explanation is available for this question!


27)   Which condition is used to verify the existence of a particular point on the root locus?

a. Amplitude
b. Frequency
c. Magnitude
d. Angle
Answer  Explanation  Related Ques

ANSWER: Angle

Explanation:
No explanation is available for this question!


28)   While specifying the angle and magnitude conditions, angles are added whereas magnitudes get ________

a. Subtracted
b. Multiplied
c. Divided
d. All of the above
Answer  Explanation  Related Ques

ANSWER: Multiplied

Explanation:
No explanation is available for this question!


29)   The magnitude & phase relationship between _________input and the steady state output is called as frequency domain.

a. Step
b. Ramp
c. Sinusoidal
d. Parabolic
Answer  Explanation  Related Ques

ANSWER: Sinusoidal

Explanation:
No explanation is available for this question!


30)   If a linear system is subjected to an input r(t) = Asin(ωt), what output will be generated?

a. c(t) = B sin (ωt + Φ)
b. c(t) = B cos (ωt + Φ)
c. c(t) = B tan (ωt + Φ)
d. c(t) = B cot (ωt + Φ)
Answer  Explanation  Related Ques

ANSWER: c(t) = B sin (ωt + Φ)

Explanation:
No explanation is available for this question!


31)   Which unit is adopted for magnitude measurement in Bode plots?

a. Degree
b. Decimal
c. Decibel
d. Deviation
Answer  Explanation  Related Ques

ANSWER: Decibel

Explanation:
No explanation is available for this question!


32)   In an octave frequency band, the ratio of f2 / f1 is equivalent to ________

a. 2
b. 4
c. 8
d. 10
Answer  Explanation  Related Ques

ANSWER: 2

Explanation:
No explanation is available for this question!


33)   In polar plots, what does each and every point represent w.r.t magnitude and angle?

a. Scalar
b. Vector
c. Phasor
d. Differentiator
Answer  Explanation  Related Ques

ANSWER: Phasor

Explanation:
No explanation is available for this question!


34)   In polar plots, if a pole is added at the origin, what would be the value of the magnitude at Ω = 0?

a. Zero
b. Infinity
c. Unity
d. Unpredictable
Answer  Explanation  Related Ques

ANSWER: Infinity

Explanation:
No explanation is available for this question!


35)   Conventional control theory is applicable to ______ systems

a. SISO
b. MIMO
c. Time varying
d. Non-linear
Answer  Explanation  Related Ques

ANSWER: SISO

Explanation:
No explanation is available for this question!


36)   State space analysis is applicable even if the initial conditions are _____

a. Zero
b. Non-zero
c. Equal
d. Not equal
Answer  Explanation  Related Ques

ANSWER: Non-zero

Explanation:
No explanation is available for this question!


37)   If an error signal e(t) of an ON-OFF controller is found to be greater than zero, what would be its output?

a. 10%
b. 50%
c. 80%
d. 100%
Answer  Explanation  Related Ques

ANSWER: 100%

Explanation:
No explanation is available for this question!


38)   Which time is responsible for introducing an error in the temperature regulation of applications associated with ON-OFF controllers?

a. Rise time
b. Dead time
c. Switching time
d. Decay time
Answer  Explanation  Related Ques

ANSWER: Dead time

Explanation:
No explanation is available for this question!


39)   Which controller has the potential to eliminate/overcome the drawback of offset in proportional controllers?

a. P-I
b. P-D
c. Both a and b
d. None of the above
Answer  Explanation  Related Ques

ANSWER: P-I

Explanation:
No explanation is available for this question!


40)   In P-I controller, what does an integral of a function compute?

a. Density of curve
b. Area under the curve
c. Volume over the curve
d. Circumference of curve
Answer  Explanation  Related Ques

ANSWER: Area under the curve

Explanation:
No explanation is available for this question!