Lecture #01
1- An interconnection of components forming a system configuration that will provide
a desired response :
a) Process
b) Control System
c) Plant
d) Other
2- It is the quantity or condition that is measured and Controlled. Normally it is the
output of the control system :
a) Controlled variable
b) Manipulated variable
c) Controller's output
d) Other
3- It is the quantity of the condition that is varied by the controller so as to affect the
output of the system :
a) Controlled variable
b) Manipulated variable
c) Controller's output
d) Other
4- The controlled variable is applied to the system so as to limit the manipulated
variable:
a) True
b) False
5- It is the desired response which is applied as input to the controller:
a) Controlled variable
b) Manipulated variable
c) Set point
d) Other
6- It is a signal that tends to adversely affect the value of the system.
a) Control Signal
b) Actuator Signal
c) Disturbance Signal
d) Other
7- Which of the following components must be placed in the feedback path :
a) Controller
b) Actuator
c) Sensor
d) Other
8- In controlling the liquid level of water tank, which of the following represents the
actuator:
a) Float
b) Valve
c) Tank
d) Other
9- In controlling the liquid level of water tank, which of the following signals is applied
to the pneumatic valve:
a) Controlled variable
b) Manipulated variable
c) Set point
d) Other
10- In controlling the liquid level of water tank, which of the following signals is applied
to the Float:
a) Controlled variable
b) Manipulated variable
c) Set point
d) Other
11- In ……………… the output has no effect on the control action:
a) Closed loop control
b) Open loop control
c) Other
12a)
b)
c)
Washing Machine is a control machine of type :
Closed loop control
Open loop control
Other
13a)
b)
c)
………………. Is more sensitive to disturbance :
Closed loop control
Open loop control
Other
14- in open loop control systems reference input is not compared with measured
output, for each reference input there is fixed operating condition. Therefore, the
accuracy of the system depends on calibration.
a) True
b) False
15- The performance of closed loop system is severely affected by the presence of
disturbances.
a) True
b) False
16- …………………………….Utilizes feedback to compare the actual output to the desired
output response.
a) Closed loop control
b) Open loop control
c) Other
17a)
b)
c)
Air conditioner is a control machine of type :
Closed loop control
Open loop control
Other
18- For controlling the liquid level of water tank by using a float to determine the
required level of the level inside the tank. This system is type of :
a) Closed loop control
b) Open loop control
c) Other
19- A system that maintains a prescribed relationship between the output and some
reference input by comparing them and using the difference as a means of control is
called open loop control.
a) True
b) False
20- A system that maintains a prescribed relationship between the output and some
reference input by comparing them and using the difference as a means of control is
called ……………………... control
a) Open loop
b) Positive feedback
c) Negative feedback
d) Feed-forward
21- The process is commonly placed on the ………..path
a) Feed- forward
b) Feed-back
c) Feed-forward or feed-back
22- It is a component of a machine that is responsible for moving and controlling a
mechanism or system.
a) Transducer
b) Plant
c) Actuator
d) Other
23- In the unity feedback system, the feedback path contain ………..
a) Sensor
b) Float
c) Tachometer
d) No component
24- It is the component that remove the noise from the manipulated variable or amplify
it.
a) Actuator
b) Configuration
c) Regulating
d) Signal conditioning
25- Commonly, the operating power of the actuator from ………
a) Controller
b) Controlled variable
c) External
d) Other
26- If the manipulated variable is described as discrete time intervals then the controller
of type……………… controller :
a) Continuous
b) Digital
For the following system answer the questions (27 - 30)
27- A/D converter is a ………………. Component
a) Actuator
b) Sensor
c) Signal conditioning
d) Other
28- Interface is a ………………. Component
a) Sensor
b) Signal conditioning
c) Actuator
d) Process
29- Heater is a ………………. Component
a) Sensor
b) Signal conditioning
c) Actuator
d) Process
30- Relay is a …………….. component
a) Sensor
b) Signal conditioning
c) Actuator
d) Process
31a)
b)
c)
d)
For open control system which of the following statements is incorrect ?
Less expensive
Recalibration is not required for maintaining the required quality of the output
Construction is simple and maintenance easy
Errors are caused by disturbances
32- A control system in which the control action is somehow dependent on the output is
known as
a) Closed loop system
b) Semi-closed loop system
c) Open system
d) None of the above
33a)
b)
c)
d)
In open loop system, the control action
depends on the size of the system
depends on system variables
depends on the input signal
independent of the output
34a)
b)
c)
d)
A good control system has all the following features except
good stability
slow response
good accuracy
sufficient power handling capacity
Lecture #03
1- The mathematical modeling of input-output behavior of a system is described as
………..
a) Differential equation
b) Linear equation
c) Stochastic equation
d) Other
2- For translational spring, the force is proportional to ………….
a) Displacement
b) Speed of movement
c) Acceleration of movement
d) Other
3- For translational damper, the force is proportional to ………….
a) Displacement
b) Speed of movement
c) Acceleration of movement
d) Other
4- The transfer function (x(S) / F(S)) of the following system is :
a)
b)
c)
d)
(1 / (M S2 + K1 + K2))
(1 / (M S2 + K1 - K2))
(1 / (M S2 + K1 S + K2))
Other
5- The transfer function (Y(S) / F(S)) of the following system is :
a)
b)
c)
d)
(1 / (m S + f + k))
(1 / (m S2 + f S + k))
(1 / (m S2 + f + k S))
Other
6- The transfer function (Y(S) / F(S)) of the following system is :
a) (1 / (M S + f + k))
b) (1 / (M S2 + f + k S))
c) (1 / (M S2 + f S + k))
d) Other
7- The transfer function (Uc(S) / Ur(S)) of the following system is :
a)
b)
c)
d)
(1 / (LC S + RC+1))
(1 / (LC S2 + RC+1))
(1 / (LC S2 + RC S+1))
Other
8- The transfer function of the following system is :
a)
b)
c)
d)
(1 / (RC S2 + 1))
(1 / (RC S + 1))
(1 / (RC S2 + C S))
Other
9- The transfer function of the following system is :
a)
b)
c)
d)
(1 / ((R1 + R2)C S + 1))
(R1C S / ((R1 + R2)C S + 1))
(R2C S / ((R1 + R2)C S + 1))
Other
10- …………………………. is the ratio of Laplace transform of the output to the Laplace
transform of the input.
a) Mathematical modeling
b) Transfer function
c) State space representation
d) Other
11- When the order of denominator polynomial is greater than the numerator
polynomial, the transfer function is said to be …………………
a) Improper
b) Proper
c) Strictly proper
d) Other
12- When the order of denominator polynomial is smaller than the numerator
polynomial, the transfer function is said to be …………………
a) Improper
b) Proper
c) Strictly proper
d) Other
13- When the order of denominator polynomial is equal to the numerator polynomial,
the transfer function is said to be …………………
a) Improper
b) Proper
c) Strictly proper
d) Other
14- Roots of denominator polynomial of a transfer function are called ……………….
a) Poles
b) Zeros
c) Controlled variables
d) Other
15- Roots of numerator polynomial of a transfer function are called ……………….
a) Poles
b) Zeros
c) Controlled variables
d) Other
16a)
b)
c)
d)
Which of the following determine the system order :
Poles
Zeros
Controlled variables
Other
17a)
b)
c)
d)
It is the frequency at which system becomes infinite:
Poles
Zeros
Controlled variables
Other
18- For any bounded input the output of the system is also bounded (BIBO) the system
is said to be ………………
a) Stable
b) Un-stable
c) Other
19a)
b)
c)
d)
Which of the following determines the stability of the system:
Poles
Zeros
Controlled variables
Other
20- If all the poles of the system lie in left half plane the system is said to be …………..
a) Asymptotically stable
b) Unstable
c) Marginally stable
d) Other
21a)
b)
c)
d)
If any of the poles lie in right half plane the system is said to be ………………….
Asymptotically stable
Unstable
Marginally stable
Other
22a)
b)
c)
d)
If pole(s) lie on imaginary axis the system is said to be ……………..
Asymptotically stable
Unstable
Marginally stable
Other
23- If poles lie on the imaginary axis, the system steady at certain level at the infinity.
a) True
b) False
24- For a closed loop system contain a process (G(s)) and a sensor (H(s)) in the feedback,
the closed loop transfer function is given by:
a) G(s)/1+G(s)H(s)
b) G(s)H(s)/1-G(s)H(s)
c) G(s)/1+G(s)H(s)
d) G(s)/1-G(s)H(s)
25a)
b)
c)
d)
The overall transfer function from block diagram reduction for cascaded blocks is :
Sum of individual gain
Product of individual gain
Difference of individual gain
Division of individual gain
26- Transfer function of the system is defined as the ratio of Laplace output to Laplace
input considering initial conditions________
a) 1
b) 2
c) 0
d) infinite
27- The advantage of block diagram representation is that it is possible to evaluate the
contribution of each component to the overall performance of the system.
a) True
b) False
Lecture #04
1- Transfer functions are used to model dynamic systems in ……………………
a) Frequency domain
b) Time domain
c) Can be frequency or time domain
d) Other
2- state space representation is a way of modeling systems in …………………..
a) Frequency domain
b) Time domain
c) Can be frequency or time domain
d) Other
3- Using state space representation, differential equations with order n can be
decomposed into ……………… first order equations.
a) Log n
b) n2
c) n
d) Other
4- In state space representation, what is the output of the following equation :
C (s I - A)-1 B + D
a) The controlled variable
b) The manipulated variable
c) The transfer function
d) Other
5- The Unforced Response can be estimated by applying u(t) as input signal.
a) True
b) False
6- In state space representation, the output of ɸ (0) is …………….
a) [0 1 ; 1 0]
b) [1 0 ; 0 1]
c) [0 0 ; 0 0]
d) Other
7- For the following function :
a)
b)
c)
d)
The name of the function is ……………….. and Laplace transform is ………….
Step , (A/S)
Impulse , (A)
Ramp , (A/S2)
Other
8- The…………….function is first integral of the …………….. function
a) Ramp , Impulse
b) Step , Ramp
c) Ramp , Step
d) Other
9- The…………….function is first derivative of the …………….. function
a) Ramp , Impulse
b) Impulse , Step
c) Ramp , Step
d) Other
10- In state space representation, ɸ (t) is estimated using the Laplace transform of which
function:
a) (s I -A)
b) (s - A)
c) (s I – A)-1
d) Other
11- The transfer function for the state representation of the continuous time LTI
system:
dq(t)/dt=A
q(t)+B
x(t)
Y(t)=C q(t)+D x(t)
is given by:
a)
b)
c)
d) D(s I-A)-1 B+C
C(s
B(s
C(s
I-A)-1
I-A)-1
I-A)-1
B+D
B+D
B+A
12- State space analysis is applicable for non-linear systems and for multiple input and
output systems.
a) True
b) False
13- 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 but R is not correct explanation of A
b) Both A and R are true and R is correct explanation of A
c) A is true but R is False
d) A is False but R is True
14a)
b)
c)
d)
Which among the following is a unique model of a system?
Transfer function
State variable
Block diagram
Other
15- Which among the following plays a crucial role in determining the state of dynamic
system?
a) State variables
b) State vector
c) State space
d) State scalar
16a)
b)
c)
d)
State space analysis is applicable even if the initial conditions are _____
Zero
Non-zero
(a) and (b)
Other
17- 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+8 s
c) 100/s2-8 s
d) 100/s2+8 s
18- The large number of differential equations are complex to be analyzed using state
space representation.
a) True
b) False
19- The poles can be estimated from state space representation using which equation:
a) (s I - A)
b) (s I - A)-1
c) (s - A)
d) Other
20- Consider state space representation of a system where :
A = [0 1 0; 0 0 1; -6 -11 -6]
The poles of the system are :
a) 1, 2 and 3
b) -1, -2 and -3
c) -1, -2 and 3
d) Other
A state space description of a spring-mass-damper system is given by the following matrices:
Answer questions (21-25)
21- The item at index (0,0) of the state transition matrix in S-domain is :
a) 1 / (S2 + 2 S + 4)
b) (S+2) / (S2 + 2 S + 4)
c) S / (S2 + 2 S + 4)
d) -4 / (S2 + 2 S + 4)
22- The item at index (2 , 2) of the state transition matrix in S-domain is :
a) 1 / (S2 + 2 S + 4)
b) (S+2) / (S2 + 2 S + 4)
c) S / (S2 + 2 S + 4)
d) -4 / (S2 + 2 S + 4)
23- The transfer function of this system is :
a) 1 / (S2 + 2 S + 4)
b) (S+2) / (S2 + 2 S + 4)
c) S / (S2 + 2 S + 4)
d) -4 / (S2 + 2 S + 4)
24- The roots of this system are :
a) -2 and -2
b) 1+2j and 1-2j
c) 1+1.73j and 1-1.73j
d) Other
25- This system is ………………
a) Asymptotically stable
b) Un-stable
c) Marginally stable
d) Other
A state space description of system as follow:
Answer questions (26 - 30)
26- The item at index (0,0) of the state transition matrix in time domain is :
a) e-t - e-2t
b) 2e-t - e-2t
c) - e-t + 2e-2t
d) -2e-t + 2e-2t
27- The item at index (1,0) of the state transition matrix in time domain is :
a) e-t - e-2t
b) 2e-t - e-2t
c) - e-t+2e-2t
d) -2e-t+2e-2t
28- The roots of this system are :
a) 1 and 2
b) -1 and -2
c) -1 and 2
d) Other
29- This system is ………………
a) Asymptotically stable
b) Un-stable
c) Marginally stable
d) Other
30- If a step input signal is applied with zero initial condition what is the output of the
system in time domain y(t) is :
a) 0.5 - e-t - 0.5 e-2t
b) 1+ 2e-t - e-2t
c) 2 - e-t+e-2t
d) 0.5 - 2e-t + 0.5e-2t
Lecture #05
1- In time-domain analysis the response of a dynamic system to an input is expressed
as a function of ………………
a) Frequency
b) S-domain
c) Time
d) Other
2- It is possible to compute the time response of a system based on ……………
a) Input signal
b) Mathematical model of the system
c) (a) and (b) together
d) Other
3- The dynamic behavior of a system is therefore judged based on mathematical model
only without need to input signal.
a) True
b) False
4- The time response of any system has component (s) such as ……….
a) Transient response
b) Steady-state response
c) (a) and (b)
d) Other
5- ………………..is the response of the system is changed from rest or equilibrium it takes
some time to settle down.
a) Transient response
b) Steady-state response
c) Equilibrium response
d) Other
6- Transient response dependents upon …………………..
a) System's poles
b) System's zeros
c) Input signal
d) Other
7- The steady-state response depends on ………………..
a) System dynamics
b) Input quantity
c) (a) and (b)
d) Other
8- For a system has a transfer function G(s) = K / (S+1), if an impulse input is applied to
it without feedback the time response of this system is ………………….
a) e-Kt
b) e-t
c) K e-t
d) Other
9- For a system has a transfer function G(s) = K / (S+1), if a step input is applied to it
without feedback the time response of this system is ………………….
a) (1 - e-Kt)
b) (1 - e-t)
c) K (1-e-t)
d) Other
10- For first order system, the time of the step response to achieve its final value
increase with increasing …………………….
a) D.C gain
b) Time constant
c) Frequency of system
d) Other
11- The impulse response is the differentiation of the ………………… response
a) Ramp
b) Step
c) Linear
d) Other
12- Changing the parameters of a second-order system can change oscillation of the
system.
a) True
b) False
13- …………………… is a measure of the degree of resistance to change in the system
output.
a) un-damped natural frequency
b) Time constant
c) Damping ratio
d) Other
14- ………………………..is the speed of oscillation of the system without damping.
a) un-damped natural frequency
b) Time constant
c) Damping ratio
d) Other
15- For a closed loop second order system, when (ξ > 1) the system response is …………….
a) Critical damping
b) Over damping
c) Under damping
d) Oscillation
16- For a closed loop second order system, when (ξ = 1) the system response is …………….
a) Critical damping
b) Over damping
c) Under damping
d) Oscillation
17- For a closed loop second order system, when ( 0 < ξ < 1) the system response is
…………….
a) Critical damping
b) Over damping
c) Under damping
d) Oscillation
18- For a closed loop second order system, when (ξ =0) the system response …………….
a) Critical damping
b) Over damping
c) Under damping
d) Oscillation
19- For a closed loop second order system, if the poles of the system are (-1- 5 j and -1
+5 j) then the system response is …………….
a) Critical damping
b) Over damping
c) Under damping
d) Oscillation
20- For a closed loop second order system, if the poles of the system are (- 5 j and +5 j)
then the system response is …………….
a) Critical damping
b) Over damping
c) Under damping
d) Oscillation
21- For a closed loop second order system, if the poles of the system are two different
real then the system response is …………….
a) Critical damping
b) Over damping
c) Under damping
d) Oscillation
22- For a closed loop second order system, if the poles of the system are two equal
imaginary without real part then the system response is …………….
a) Critical damping
b) Over damping
c) Under damping
d) Oscillation
23a)
b)
c)
d)
The system response that has overshoot is a …………………….
Critical damping
Over damping
Under damping
Other
24- Natural Un-damped Frequency has unit of ……………
a) rad
b) second
c) rad / second
d) Other
25- Distance from the origin of S-plane to pole is ………………..
a) Time constant
b) Damping ratio
c) Un-damped Frequency
d) Other
26- Cosine of the angle between vector connecting origin and pole and –ve real axis is
…………..
a) Time constant
b) Damping ratio
c) Un-damped Frequency
d) Other
27- ……………… is the time required for the response to reach half the final value the very
first time.
a) Rise time
b) Delay time
c) Peak time
d) Settling time
28- …………………..is the time required for the response to rise from 10% to 90 of its final
value.
a) Rise time
b) Delay time
c) Peak time
d) Settling time
29- …………………… is the time required for the response to reach the first peak of the
overshoot.
a) Rise time
b) Delay time
c) Peak time
d) Settling time
30- ………………….is the time required for the response curve to reach and stay within a
range about the final value of size specified by absolute percentage of the final
value.
a) Rise time
b) Delay time
c) Peak time
d) Settling time
31- …………………….is the maximum peak value of the response curve measured from
unity.
a) Steady state output
b) Transient output
c) Maximum overshoot
d) Other
32- The amount of the maximum (percent) overshoot directly indicates the relative
stability of the system.
a) True
b) False
A closed loop control system has two system as follow:
Forward path system:
Backward path :
( )
(
)
( )
It is desired to design the system so that the damping ratio (ξ) is 0.5 and the rise time (tr) is
0.6045 sec.
Answer questions (33 - 39) based on these information.
33- The value of un-damped frequency (ωn) is……………………
a) 2
b) 4
c) 6
d) Other
34- To achieve the desired response, the value of (k) is …………….
a) 4
b) 8
c) 16
d) Other
35- To achieve the desired response, the value of (z) is …………….
a) 0.125
b) 0.25
c) 0.5
d) Other
36- The delay time (td) is …………..
a) 0.15
b) 0.27
c) 0.45
d) Other
37- The maximum overshoot is ……………..
a) 0.16
b) 0.24
c) 0.48
d) Other
38- The peak time is ………….
a) 0.3
b) 0.6
c) 0.9
d) Other
39- The settling time (5%) criterion is…………….
a) 0.5
b) 1
c) 1.5
d) Other
Lecture #06
1- System must suffer from steady state error for any type of input.
a) True
b) False
2- A system may have no steady-state error to a step input, but the same system may
exhibit nonzero steady-state error to a ramp input.
a) True
b) False
3- steady-state error is existed based on ………..
a) Input type
b) Open loop transfer function of system
c) (a) and (b)
d) Other
4- For the system : G(s) = (s+1) (s+2) / s3 (s+3)(s+4), this system has type ………..
a) 2
b) 3
c) 4
d) Other
5- ………………… error constant is the value of the transfer function in s-domain for s=0
a) static velocity
b) static acceleration
c) static position
d) Other
6- The higher static position error constant as the higher steady state error for step
input.
a) True
b) False
7- ………………… error constant is the first differential transfer function in s-domain for
s=0.
a) static velocity
b) static acceleration
c) static position
d) Other
8- For system of type 0 and step input the steady state error is …….
a) Constant
b) Infinity
c) Zero
d) Other
9- For system of type 1 and acceleration input the steady state error is …….
a) Constant
b) Infinity
c) Zero
d) Other
10- For system of type 2 and ramp input the steady state error is …….
a) Constant
b) Infinity
c) Zero
d) Other
For a system : G(s) = 100 (s+2) / s (s+8) answer questions (11- 15)
11- The type of system is …………
a) 0
b) 1
c) 2
d) Other
12- The static position constant error is ……………….
a) Constant
b) Infinity
c) Zero
d) Other
13- The static velocity constant error is ……………….
a) Constant
b) Infinity
c) Zero
d) Other
14- For step input, the steady state error is ……………..
a) Constant
b) Infinity
c) Zero
d) Other
15- For step input, the steady state error is ……………..
a) Constant
b) Infinity
c) Zero
d) Other
16- Routh-Hurwitz Stability Criterion is used to estimate ……………
a) Steady state error
b) Stability
c) Overshoot
d) Other
17- The Routh-Hurwitz criterion states that “the number of roots of the characteristic
equation with positive real parts is equal to the number of parameters in the first
column of the Routh array.
a) True
b) False
18- Routh-Hurwitz criterion test the stability of the system by estimating the closed loop
poles.
a) True
b) False
19- For the system shown below :
According to Routh-Hurwitz criterion what is the range of K to make the closed loop
system is stable.
a)
K>0
b)
0 < k < 7.5
c)
K > 7.5
d)
Other
20- For the closed loop characteristics equation :
s 3  3s 2  3s  1  K = 0
a)
b)
c)
d)
According to Routh-Hurwitz criterion what is the range of K to make the closed loop
system is stable.
K > -1
-1 < k < 8
K>8
Other