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All questions of Basics of Control System & Transfer Function for Electrical Engineering (EE) Exam
Can you explain the answer of this question below:
The sum of the gains of the feedback paths in the signal flow graph shown in fig. is
A: af + be + cd
B: af + be + cd+abef + bcdeC: af + be + cd + abef + abcdefD: af + be + cd + cbef + bcde + abcdefThe answer is a.
|
Phanindra Varma N answered |
Answer is B because ut can form only individual loop gains
The block diagram of a system is shown in fig.The closed loop transfer function of this system is
a)
b) 
c) 
d) 
Correct answer is 'D'. Can you explain this answer?
a)
b)
c)
d)
Correct answer is 'D'. Can you explain this answer?
|
Nitya Ahuja answered |
Consider the block diagram as SFG. There are two feedback loop -G1G2H1 and -G2G3H2 and one forward path G1G2 G3 . So (D) is correct option.
Linear system obeys- a)reciprocity theorem
- b)principle of maximum power transfer
- c)both (a) and (b)
- d)none of the above
Correct answer is option 'C'. Can you explain this answer?
Linear system obeys
a)
reciprocity theorem
b)
principle of maximum power transfer
c)
both (a) and (b)
d)
none of the above
|
|
Sanvi Kapoor answered |
Linear system obeys both reciprocity theorem and principle of maximum power transfer.
In the signal flow graph of figure y/x equalsa) 3b) 2c) 5/2d) None of the aboveCorrect answer is option 'B'. Can you explain this answer?
|
Aditya Deshmukh answered |
The answer is b.
P1 = 5 x 2 x 1 = 10
P1 = 5 x 2 x 1 = 10
L1 = - 4
Y/X = 10/1-(-4) = 2
For the system shown in fig. transfer function C(s) R(s) is
- a)
- b)
- c)
- d)
Correct answer is option 'B'. Can you explain this answer?
For the system shown in fig. transfer function C(s) R(s) is
a)
b)
c)
d)
|
Gate Gurus answered |
Consider the block diagram as a SFG. Two forward path G1G2 and G3 and three loops -G1G2 H2, -G2H1, -G3 H2
There are no nontouching loop. So (B) is correct.
There are no nontouching loop. So (B) is correct.
For the signal flow graph shown in fig. an equivalent graph is
- a)
- b)
- c)
- d)
Correct answer is option 'C'. Can you explain this answer?
For the signal flow graph shown in fig. an equivalent graph is
a)
b)
c)
d)
|
Prince S answered |
Is there any difference in opinion A and option C. Both could be answers.
For the block diagram shown in fig. the numerator of transfer function is
- a)
- b)
- c)
- d)none of these
Correct answer is option 'A'. Can you explain this answer?
For the block diagram shown in fig. the numerator of transfer function is
a)
b)
c)
d)
none of these
|
Zoya Sharma answered |
SFG
P1 = G2G5G6 , P2 = G3G5G6, P3 = G3G6 , P4 = G4G6
If any path is deleted, there would not be any loop.
Hence Δ1 = Δ2 = Δ3 = Δ4 = 1
P1 = G2G5G6 , P2 = G3G5G6, P3 = G3G6 , P4 = G4G6
If any path is deleted, there would not be any loop.
Hence Δ1 = Δ2 = Δ3 = Δ4 = 1
The principle of homogeneity and superposition are applied to:a)Linear time variant systemsb)Nonlinear time invariant systemsc)Linear time invariant systemsd)Nonlinear time invariant systemsCorrect answer is 'C'. Can you explain this answer?
|
|
Aditya Deshmukh answered |
Superposition theorem states that for two signals, additive and homogeneity property must be satisfied and that is applicable for the Linear time variant (LTI) systems.
The output of the feedback control system must be a function of:
- a)Reference input
- b)Reference output
- c)Output and feedback signal
- d)Input and feedback signal
Correct answer is option 'D'. Can you explain this answer?
The output of the feedback control system must be a function of:
a)
Reference input
b)
Reference output
c)
Output and feedback signal
d)
Input and feedback signal
|
|
Athira Reddy answered |
Explanation: In a feedback control system, the output is determined by a combination of the input signal and the feedback signal. The input signal is the desired output or reference, while the feedback signal is a portion of the actual output that is fed back into the system to compare with the input. This comparison helps the system to adjust its output to minimize the error between the input and the actual output. By considering both the input and feedback signals, the system can continuously adapt and achieve the desired output.
Assertion (A): Closed loop control systems are known as feedback control systems.
Reason (R): In closed loop control systems, the control action is dependent on the desired output.- a)Both A and R are true and R is a correct explanation of A.
- b)Both A and R are true but R is not a correct explanation of A.
- c)A is true but R is false.
- d)A is false but R is true.
Correct answer is option 'A'. Can you explain this answer?
Assertion (A): Closed loop control systems are known as feedback control systems.
Reason (R): In closed loop control systems, the control action is dependent on the desired output.
Reason (R): In closed loop control systems, the control action is dependent on the desired output.
a)
Both A and R are true and R is a correct explanation of A.
b)
Both A and R are true but R is not a correct explanation of A.
c)
A is true but R is false.
d)
A is false but R is true.
|
|
Sanvi Kapoor answered |
- In closed loop system there is the presence of a feedback path and this feedback path has connected from output of the system to the input of the system.
- The whole operation is controlled by the output of the system.
The most commonly used input signal(s) in control system is/are- a)ramp or velocity function
- b)step function
- c)accelerating function
- d)all of the above
Correct answer is option 'B'. Can you explain this answer?
The most commonly used input signal(s) in control system is/are
a)
ramp or velocity function
b)
step function
c)
accelerating function
d)
all of the above
|
|
Sarita Yadav answered |
A step function is commonly used as a input signal in a control system because:
- IF we go through first order system, here we calculate steady-state error by providing input function then we got zero steady-state error.
- Actually in step function, output follows input always that means steady error is minimum.
Consider the List I and List II
The correct match is- a)2 1 3 4
- b)2 1 4 3
- c)1 2 4 3
- d)1 2 3 4
Correct answer is option 'B'. Can you explain this answer?
Consider the List I and List II
The correct match is
a)
2 1 3 4
b)
2 1 4 3
c)
1 2 4 3
d)
1 2 3 4
|
Om Pillai answered |
P. P1 = ab, Δ = 1, L = 0 ,T = ab
Q1 P1 = a, P2 = 6 , Δ = 1, L = Δk = 0,T = a+b
R. P1 = a, L1 = b, Δ = 1 - b, Δ1 =1,
S. P1 = a, L1 = ab, Δ = 1 - ab, Δ1 = 1,
Q1 P1 = a, P2 = 6 , Δ = 1, L = Δk = 0,T = a+b
R. P1 = a, L1 = b, Δ = 1 - b, Δ1 =1,
S. P1 = a, L1 = ab, Δ = 1 - ab, Δ1 = 1,
Assuming zero initial condition, the response y(t) of the system given below to a unit step input u(t) is
- a)u(t)
- b)t.u(t)
- c)t2/2.u(t)
- d)e-tu(t)
Correct answer is option 'B'. Can you explain this answer?
Assuming zero initial condition, the response y(t) of the system given below to a unit step input u(t) is
a)
u(t)
b)
t.u(t)
c)
t2/2.u(t)
d)
e-tu(t)
|
Luminary Institute answered |
Laplace transform of u(t) is given by
Taking Inverse Laplace transform
y(t) = t.u(t)
Assertion (A): If the number of zeros are less than the number of poles (i.e. Z < P), we say that there are zeros at infinity and the order of such zeros is P-Z
Reason (R): The value of the transfer function becomes zero for s tends to zero.- a)Both A and R are true and R is a correct explanation of A.
- b)Both A and R are true but R is not a correct explanation of A.
- c)A is true but R is false.
- d)A is false but R is true.
Correct answer is option 'C'. Can you explain this answer?
Assertion (A): If the number of zeros are less than the number of poles (i.e. Z < P), we say that there are zeros at infinity and the order of such zeros is P-Z
Reason (R): The value of the transfer function becomes zero for s tends to zero.
Reason (R): The value of the transfer function becomes zero for s tends to zero.
a)
Both A and R are true and R is a correct explanation of A.
b)
Both A and R are true but R is not a correct explanation of A.
c)
A is true but R is false.
d)
A is false but R is true.
|
Uday Kumar answered |
For Z < P,
∴ Here, number of zeros = 1 and no. of poles = 2
∴ P - Z = 1
When s →∞, transfer function becomes zero. Thus, there is one zero (P - Z = 1) at infinity. Thus, assertion is true.
Since value of transfer function becomes zero as s →∞ therefore, reason is false.
∴ Here, number of zeros = 1 and no. of poles = 2
∴ P - Z = 1
When s →∞, transfer function becomes zero. Thus, there is one zero (P - Z = 1) at infinity. Thus, assertion is true.
Since value of transfer function becomes zero as s →∞ therefore, reason is false.
For the system shown in the figure, Y(s)/X(s) = _________. (Answer in integer )
Correct answer is between '0.95,1.05'. Can you explain this answer?
For the system shown in the figure, Y(s)/X(s) = _________. (Answer in integer )
|
Cstoppers Instructors answered |
The circuit is redrawn as shown:
[X(s) – Y(s)] G(s) + X(s) = Y(s)
Given G(s) = 2
(X(s) – Y(s)) 2 + X(s) = Y(s)
= 2 X(s) + X(s) = Y(s) + 2Y(s)
= 3 X(s) = 3 Y(s)
The step response of a system is given by
c(t) = 1 + 0.25 e-50t - 1.25e-10t
The steady state gain of the transfer function in time constant form will be- a)1
- b)7
- c)-5
- d)-7
Correct answer is option 'A'. Can you explain this answer?
The step response of a system is given by
c(t) = 1 + 0.25 e-50t - 1.25e-10t
The steady state gain of the transfer function in time constant form will be
c(t) = 1 + 0.25 e-50t - 1.25e-10t
The steady state gain of the transfer function in time constant form will be
a)
1
b)
7
c)
-5
d)
-7
|
Ritika Menon answered |
Given, c(t) = 1 + 0.25 e-50t - 1.25e-10t
Thus,C(s)/R(s) is in time constant form having steady state gain = 1.
Thus,C(s)/R(s) is in time constant form having steady state gain = 1.
A linear system with H(s) = 1/s is excited by a unit step function input. The output for t > 0 is given by- a)δ(t)
- b)1
- c)t
- d)t2
Correct answer is option 'C'. Can you explain this answer?
A linear system with H(s) = 1/s is excited by a unit step function input. The output for t > 0 is given by
a)
δ(t)
b)
1
c)
t
d)
t2
|
Meghana Gupta answered |
Given Information:
The transfer function of the linear system is H(s) = 1/s, and it is excited by a unit step function input.
Output for t > 0:
The output for t > 0 can be found by taking the inverse Laplace transform of the product of the input and the transfer function.
Calculation:
- The Laplace transform of a unit step function is 1/s.
- Given transfer function H(s) = 1/s.
- The output Y(s) can be calculated by Y(s) = H(s) * X(s), where X(s) is the Laplace transform of the unit step function.
- Substituting the values, Y(s) = 1/s * 1/s = 1/s^2.
- Taking the inverse Laplace transform of Y(s), we get y(t) = t.
Conclusion:
The correct answer is option 'C', which is t. The output for t > 0 in this linear system excited by a unit step function input is a ramp function with a slope of 1.
The transfer function of the linear system is H(s) = 1/s, and it is excited by a unit step function input.
Output for t > 0:
The output for t > 0 can be found by taking the inverse Laplace transform of the product of the input and the transfer function.
Calculation:
- The Laplace transform of a unit step function is 1/s.
- Given transfer function H(s) = 1/s.
- The output Y(s) can be calculated by Y(s) = H(s) * X(s), where X(s) is the Laplace transform of the unit step function.
- Substituting the values, Y(s) = 1/s * 1/s = 1/s^2.
- Taking the inverse Laplace transform of Y(s), we get y(t) = t.
Conclusion:
The correct answer is option 'C', which is t. The output for t > 0 in this linear system excited by a unit step function input is a ramp function with a slope of 1.
Which of the following is not the feature of modern control systems?- a)No oscillation
- b)Quick response
- c)Accuracy
- d)Correct power level
Correct answer is option 'A'. Can you explain this answer?
Which of the following is not the feature of modern control systems?
a)
No oscillation
b)
Quick response
c)
Accuracy
d)
Correct power level
|
Mita Mehta answered |
For a good control system the speed of response and stability must be high and for the slow and sluggish response is not used and undesirable.
A standard signal used for comparison in a closed-loop control system is called the- a)step input
- b)reference input
- c)error input
- d)ramp input
Correct answer is option 'B'. Can you explain this answer?
A standard signal used for comparison in a closed-loop control system is called the
a)
step input
b)
reference input
c)
error input
d)
ramp input
|
Manoj Chaudhary answered |
Reference Input in Closed-Loop Control System
In a closed-loop control system, a standard signal is used for comparison with the system output to generate an error signal. This error signal is then used to adjust the system input to minimize the difference between the desired output and the actual output. The standard signal used for comparison is called the reference input.
Definition of Reference Input
The reference input is the desired output of the system. It represents the setpoint or target value that the system is designed to achieve. The reference input is usually a constant value or a time-varying signal that the system follows. The closed-loop control system continuously compares the reference input with the actual system output and generates an error signal that is used to adjust the system input to minimize the difference between the two.
Importance of Reference Input
The reference input is an essential component of a closed-loop control system. The accuracy and stability of the system depend on how well the reference input represents the desired output. The reference input must be carefully selected to ensure that the system responds correctly to changes in the desired output.
Types of Reference Input
The reference input can be of different types, depending on the application and the desired output. Some common types of reference input are:
- Step Input: A step input is a sudden change in the reference input that occurs at a specific time. It is commonly used to test the system's response to a sudden change in the desired output.
- Ramp Input: A ramp input is a gradual change in the reference input over time. It is commonly used to test the system's response to a slow change in the desired output.
- Sinusoidal Input: A sinusoidal input is a periodic signal that represents a repetitive pattern in the desired output. It is commonly used to test the system's response to a periodic disturbance in the desired output.
Conclusion
In conclusion, the reference input is a critical component of a closed-loop control system. It represents the desired output of the system and is used for comparison with the actual system output to generate an error signal. The accuracy and stability of the system depend on how well the reference input represents the desired output. Therefore, it is essential to carefully select the reference input based on the application and the desired output.
In a closed-loop control system, a standard signal is used for comparison with the system output to generate an error signal. This error signal is then used to adjust the system input to minimize the difference between the desired output and the actual output. The standard signal used for comparison is called the reference input.
Definition of Reference Input
The reference input is the desired output of the system. It represents the setpoint or target value that the system is designed to achieve. The reference input is usually a constant value or a time-varying signal that the system follows. The closed-loop control system continuously compares the reference input with the actual system output and generates an error signal that is used to adjust the system input to minimize the difference between the two.
Importance of Reference Input
The reference input is an essential component of a closed-loop control system. The accuracy and stability of the system depend on how well the reference input represents the desired output. The reference input must be carefully selected to ensure that the system responds correctly to changes in the desired output.
Types of Reference Input
The reference input can be of different types, depending on the application and the desired output. Some common types of reference input are:
- Step Input: A step input is a sudden change in the reference input that occurs at a specific time. It is commonly used to test the system's response to a sudden change in the desired output.
- Ramp Input: A ramp input is a gradual change in the reference input over time. It is commonly used to test the system's response to a slow change in the desired output.
- Sinusoidal Input: A sinusoidal input is a periodic signal that represents a repetitive pattern in the desired output. It is commonly used to test the system's response to a periodic disturbance in the desired output.
Conclusion
In conclusion, the reference input is a critical component of a closed-loop control system. It represents the desired output of the system and is used for comparison with the actual system output to generate an error signal. The accuracy and stability of the system depend on how well the reference input represents the desired output. Therefore, it is essential to carefully select the reference input based on the application and the desired output.
Consider the signal flow graphs shown in fig. The transfer 2 is of the graph
- a)a
- b)b
- c)b and c
- d)a, b and c
Correct answer is option 'B'. Can you explain this answer?
Consider the signal flow graphs shown in fig. The transfer 2 is of the graph
a)
a
b)
b
c)
b and c
d)
a, b and c
|
Ishani Chauhan answered |
There are no loop in any graph. So option (B) is correct.
A ramp function occurs at t = a. It's Laplace transform is- a)e-as
- b)e-as/s
- c)e-as/s2
- d)None of these
Correct answer is option 'D'. Can you explain this answer?
A ramp function occurs at t = a. It's Laplace transform is
a)
e-as
b)
e-as/s
c)
e-as/s2
d)
None of these
|
Amar Sengupta answered |
Ramp function occurring at t = 0 is denoted by r(t) = tu(t).
Ramp function occurring at t - a will be denoted
Ramp function occurring at t - a will be denoted
As compared to a closed loop system, an open loop system is
- a)more stable but less accurate
- b)less stable as well as less accurate
- c)more stable as well as more accurate
- d)less stable but more accurate
Correct answer is option 'A'. Can you explain this answer?
As compared to a closed loop system, an open loop system is
a)
more stable but less accurate
b)
less stable as well as less accurate
c)
more stable as well as more accurate
d)
less stable but more accurate
|
|
Sanvi Kapoor answered |
As compared to closed loop system an open loop control system is more stable as all its roots are in left half of s plane only, but it less accurate since there is no feedback to measure the output value and compare it with the input value.
The phenomena of ‘limit cycles’ and ‘jump resonance’ are observed in- a)linear systems
- b)distributed systems
- c)non-linear systems
- d)discrete time systems
Correct answer is option 'C'. Can you explain this answer?
The phenomena of ‘limit cycles’ and ‘jump resonance’ are observed in
a)
linear systems
b)
distributed systems
c)
non-linear systems
d)
discrete time systems
|
Harshitha Pillai answered |
Globalization has brought about significant changes in the world economy, politics, culture, and society. It refers to the integration and interdependence of countries, economies, and people across the globe, resulting from increased trade, investment, and communication.
Globalization has led to the growth of multinational corporations, which have expanded their operations beyond their home countries, creating jobs and generating wealth. It has also resulted in the growth of international trade, leading to greater specialization and efficiency in production.
However, globalization has also led to increased inequality between countries and within societies, as some countries and individuals benefit more from the global economy than others. It has also led to the erosion of traditional cultures and values, as Western influences spread throughout the world.
Overall, globalization is a complex and multifaceted phenomenon that has both positive and negative effects on the world economy, politics, culture, and society.
Globalization has led to the growth of multinational corporations, which have expanded their operations beyond their home countries, creating jobs and generating wealth. It has also resulted in the growth of international trade, leading to greater specialization and efficiency in production.
However, globalization has also led to increased inequality between countries and within societies, as some countries and individuals benefit more from the global economy than others. It has also led to the erosion of traditional cultures and values, as Western influences spread throughout the world.
Overall, globalization is a complex and multifaceted phenomenon that has both positive and negative effects on the world economy, politics, culture, and society.
In the signal flow graph shown in fig. the sum of loop gain of non-touching loops is
a) 
b) 
c) 
d) 
Correct answer is option 'A'. Can you explain this answer?
a)
b)
c)
d)
Correct answer is option 'A'. Can you explain this answer?
|
santhosh kalyani answered |
Total 4 loops are there, among them only 2 loops are non touching( don't have any node or edge(path) in common)and the loop gains are t44 and t23xt32 so the sum is t44+t23xt32
The impulse response of a linear time invariant system is a unit step function. The transfer function of this system would be- a)1
- b)1/s2
- c)s
- d)1/s
Correct answer is option 'D'. Can you explain this answer?
The impulse response of a linear time invariant system is a unit step function. The transfer function of this system would be
a)
1
b)
1/s2
c)
s
d)
1/s
|
Siddharth Khanna answered |
Impulse response,
c(t) = u(t)
We now that,
(impulse response) - Transfer function = 
∴
c(t) = u(t)
We now that,
(impulse response) - Transfer function = ∴
Assertion (A): The control system which operates on the time basis is an open loop system.
Reason (R): A field control d.c. motor is an example of open loop system.- a)Both A and R are true and R is the correct explanation of A.
- b)Both A and R are true but R is not the correct explanation of A.
- c)A is true but R is false.
- d)A is false but R is true.
Correct answer is option 'B'. Can you explain this answer?
Assertion (A): The control system which operates on the time basis is an open loop system.
Reason (R): A field control d.c. motor is an example of open loop system.
Reason (R): A field control d.c. motor is an example of open loop system.
a)
Both A and R are true and R is the correct explanation of A.
b)
Both A and R are true but R is not the correct explanation of A.
c)
A is true but R is false.
d)
A is false but R is true.
|
Sandeep Sen answered |
The control system which operates on the time basis is an open loop system. For example, in automatic control of traffic, the time for each lamp (red, yellow and green) is fixed. The operation of each lamp does not depends upon the density of the traffic but depends upon the fixed time. Hence, assertion is true.
Reason is also true but, it is not the correct explanation of assertion.
Reason is also true but, it is not the correct explanation of assertion.
Non-minimum phase transfer function is defined as the transfer function
- a)which has zeros and poles only in the left-half s-plane
- b)which has zeroes & poles in the right-half s-plane
- c)Both A & B
- d)None of these
Correct answer is option 'B'. Can you explain this answer?
Non-minimum phase transfer function is defined as the transfer function
a)
which has zeros and poles only in the left-half s-plane
b)
which has zeroes & poles in the right-half s-plane
c)
Both A & B
d)
None of these
|
Tanvi Sarkar answered |
And poles in both the left-half and right-half s-plane
c)which has at least one zero in the right-half s-plane
d)which has at least one pole in the right-half s-plane
The correct answer is d) which has at least one pole in the right-half s-plane. This means that the transfer function has at least one factor in the denominator that is of the form (s - a), where a is a positive real number. Such a factor gives rise to an exponential term e^(at) in the time-domain response, which grows with time instead of decaying. This makes the system non-minimum phase, since it cannot be stabilized by feedback alone.
c)which has at least one zero in the right-half s-plane
d)which has at least one pole in the right-half s-plane
The correct answer is d) which has at least one pole in the right-half s-plane. This means that the transfer function has at least one factor in the denominator that is of the form (s - a), where a is a positive real number. Such a factor gives rise to an exponential term e^(at) in the time-domain response, which grows with time instead of decaying. This makes the system non-minimum phase, since it cannot be stabilized by feedback alone.
In the signal flow graph shown in fig. the gain C/R is
- a)44/23
- b)29/19
- c)44/19
- d)29/11
Correct answer is option 'A'. Can you explain this answer?
In the signal flow graph shown in fig. the gain C/R is
a)
44/23
b)
29/19
c)
44/19
d)
29/11
|
Aim It Academy answered |
P1 = 2 x 3 x 4 = 24 , P2 = 1 x 5 x 1 = 5
L1 = -2, L2 = -3, L3 = -4, L4 = -5,
L1L3 = 8, Δ = 1 -(-2 - 3 - 4 - 5) + 8 = 23, Δ1 = 1, Δ2 = 1 - (-3) = 4,
L1 = -2, L2 = -3, L3 = -4, L4 = -5,
L1L3 = 8, Δ = 1 -(-2 - 3 - 4 - 5) + 8 = 23, Δ1 = 1, Δ2 = 1 - (-3) = 4,
The transfer function is applicable to- a)linear and time-variant systems
- b)linear systems only
- c)linear and time-invariant systems
- d)non-linear systems only
Correct answer is option 'C'. Can you explain this answer?
The transfer function is applicable to
a)
linear and time-variant systems
b)
linear systems only
c)
linear and time-invariant systems
d)
non-linear systems only
|
|
Ameya Nambiar answered |
Transfer function is applicable to only linear and time-variant systems.
As compared to a closed loop system, an open loop system is- a)slow and more reliable
- b)fast and more reliable
- c)fast and less reliable
- d)slow and less reliable
Correct answer is option 'C'. Can you explain this answer?
As compared to a closed loop system, an open loop system is
a)
slow and more reliable
b)
fast and more reliable
c)
fast and less reliable
d)
slow and less reliable
|
|
Sanvi Kapoor answered |
The main difference between an open-loop system and a closed-loop system is that the closed-loop system has the ability to self-correct while the open-loop system doesn't. Consequently, closed-loop systems are often called feedback control systems while open-loop systems are also known as non-feedback controls.
The unit impulse response of a certain system is found to be e-8t. Its transfer function is _______.- a)
- b)
- c)
- d)
Correct answer is option 'B'. Can you explain this answer?
The unit impulse response of a certain system is found to be e-8t. Its transfer function is _______.
a)
b)
c)
d)
|
|
Sarita Yadav answered |
The impulse response is defined as the output of an LTI system due to a unit impulse signal input being applied at time t = 0.
y(t) = h(t) x(t) = h(t) δ(t)
where δ(t) is the unit impulse function and h(t) is the unit impulse response of a continuous-time LTI system.
Calculations:-
Given-
y(t) = e-8t
x(t) = δ(t)
For calculating the transfer function convert the time domain response into Laplace or S domain.
Assertion (A): Feedback in control system improves the time response of the system.
Reason (R): Time constant of an open loop system is less than the time constant of a closed loop system.- a)Both A and R are true and R is a correct explanation of A.
- b)Both A and R are true but R is not a correct explanation of A.
- c)A is true but R is false.
- d)A is false but R is true.
Correct answer is option 'C'. Can you explain this answer?
Assertion (A): Feedback in control system improves the time response of the system.
Reason (R): Time constant of an open loop system is less than the time constant of a closed loop system.
Reason (R): Time constant of an open loop system is less than the time constant of a closed loop system.
a)
Both A and R are true and R is a correct explanation of A.
b)
Both A and R are true but R is not a correct explanation of A.
c)
A is true but R is false.
d)
A is false but R is true.
|
Shraddha Kaur answered |
Time constant of open loop system is more than that of closed loop system. Lesser is the time constant of the system, faster is its' time response.
Consider the following statements:
1. Closed loop system is less sensitive to variations in feedback path parameters than variations in forward path parameters.
2. Feedback can improve the stability or may be harmful to stability if it is not properly designed and applied.
3. Feedback controls the time response of the system by adjusting the location of poles. Q. Which of the these statements are correct?- a)2 and 3 only
- b)1 and 2 only
- c)2 only
- d)1,2 and 3
Correct answer is option 'A'. Can you explain this answer?
Consider the following statements:
1. Closed loop system is less sensitive to variations in feedback path parameters than variations in forward path parameters.
2. Feedback can improve the stability or may be harmful to stability if it is not properly designed and applied.
3. Feedback controls the time response of the system by adjusting the location of poles.
1. Closed loop system is less sensitive to variations in feedback path parameters than variations in forward path parameters.
2. Feedback can improve the stability or may be harmful to stability if it is not properly designed and applied.
3. Feedback controls the time response of the system by adjusting the location of poles.
Q. Which of the these statements are correct?
a)
2 and 3 only
b)
1 and 2 only
c)
2 only
d)
1,2 and 3
|
Preethi Deshpande answered |
For the closed loop control system shown above, let, H = C/R transfer function.
Thus, closed loop system is more sensitive to variation in feedback path parameters than variation in forward path parameters. Hence statement-1 is false. Thus, statements 2 and 3 are only correct.
The Laplace transform of unity function is- a)1
- b) zero
- c) s
- d)1/s
Correct answer is option 'D'. Can you explain this answer?
The Laplace transform of unity function is
a)
1
b)
zero
c)
s
d)
1/s
|
Jatin Mukherjee answered |
The laplace transform of unity function i.e.
A control system is said to be robust when- a)it has low sensitivities
- b)it is stable over a wide range of parameter variation
- c)both (a) and (b)
- d)neither (a) nor (b)
Correct answer is option 'C'. Can you explain this answer?
A control system is said to be robust when
a)
it has low sensitivities
b)
it is stable over a wide range of parameter variation
c)
both (a) and (b)
d)
neither (a) nor (b)
|
Bhaskar Unni answered |
Robustness is an important characteristic of a control system, as it determines how well the system can perform in the presence of uncertainties and disturbances. A robust control system is able to maintain stability and optimal performance over a wide range of parameter variations.
Sensitivity:
Sensitivity refers to how the system responds to changes in its parameters. A control system with low sensitivities means that it is less affected by variations in its parameters. In other words, small changes in the system's parameters do not result in significant changes in the system's performance. Low sensitivities are desirable because they indicate that the system is less vulnerable to uncertainties and disturbances.
Stability:
Stability is a fundamental requirement for any control system. A stable control system maintains a desired output in the presence of disturbances and uncertainties. It ensures that the system does not exhibit oscillatory or diverging behavior, which can lead to instability. A control system that is stable over a wide range of parameter variation is considered to be robust.
Robustness:
The combination of low sensitivities and stability makes a control system robust. When a control system has low sensitivities, it means that it is not highly influenced by parameter variations. This allows the system to maintain its desired performance even when there are changes in the parameters. Additionally, when a control system is stable over a wide range of parameter variation, it means that it can adapt to different operating conditions without losing stability. This adaptability is a key characteristic of a robust control system.
Conclusion:
In conclusion, a control system is said to be robust when it has both low sensitivities and stability over a wide range of parameter variation. This means that the system is able to maintain its desired performance despite uncertainties and disturbances. Robust control systems are desirable because they are more reliable and can handle a variety of operating conditions.
Sensitivity:
Sensitivity refers to how the system responds to changes in its parameters. A control system with low sensitivities means that it is less affected by variations in its parameters. In other words, small changes in the system's parameters do not result in significant changes in the system's performance. Low sensitivities are desirable because they indicate that the system is less vulnerable to uncertainties and disturbances.
Stability:
Stability is a fundamental requirement for any control system. A stable control system maintains a desired output in the presence of disturbances and uncertainties. It ensures that the system does not exhibit oscillatory or diverging behavior, which can lead to instability. A control system that is stable over a wide range of parameter variation is considered to be robust.
Robustness:
The combination of low sensitivities and stability makes a control system robust. When a control system has low sensitivities, it means that it is not highly influenced by parameter variations. This allows the system to maintain its desired performance even when there are changes in the parameters. Additionally, when a control system is stable over a wide range of parameter variation, it means that it can adapt to different operating conditions without losing stability. This adaptability is a key characteristic of a robust control system.
Conclusion:
In conclusion, a control system is said to be robust when it has both low sensitivities and stability over a wide range of parameter variation. This means that the system is able to maintain its desired performance despite uncertainties and disturbances. Robust control systems are desirable because they are more reliable and can handle a variety of operating conditions.
Which of the following is not correctly matched?
(CLCS = Closed Loop Control System and OLCS = Open Loop Control System)
- a)a
- b)b
- c)c
- d)d
Correct answer is option 'C'. Can you explain this answer?
Which of the following is not correctly matched?
(CLCS = Closed Loop Control System and OLCS = Open Loop Control System)
(CLCS = Closed Loop Control System and OLCS = Open Loop Control System)
a)
a
b)
b
c)
c
d)
d
|
Imtiaz Ahmad answered |
Radar tracking systems are generally closed-loop systems because they use feedback to continuously adjust and track an object. However, if this refers to the initial detection phase, it might not use feedback, making it an open-loop system. Without additional context, this might be incorrect.
The difference between the output response and the reference signal is known as the _____ signal.- a)actuating
- b)bias
- c)velocity
- d)none of these
Correct answer is option 'A'. Can you explain this answer?
The difference between the output response and the reference signal is known as the _____ signal.
a)
actuating
b)
bias
c)
velocity
d)
none of these
|
Uday Saini answered |
The Actuating Signal in Control Systems
In a control system, the output response is compared with the reference signal to determine the error. The difference between the two signals is known as the actuating signal. This signal is crucial in determining the corrective action that needs to be taken to reduce the error and achieve the desired output response.
The actuating signal is usually a voltage or current signal that is used to control the system's input or output. It is generated by the controller and is used to activate the actuator, which in turn, adjusts the system's output.
The actuating signal is an essential component of a control system as it determines the corrective action that needs to be taken to reduce the error and achieve the desired output response. In the absence of an actuating signal, the control system would not be able to correct the error and achieve the desired output.
The Bias Signal
The bias signal is a constant signal that is added to the input or output of a system. It is used to offset the system's response and to ensure that it operates within a specific range. The bias signal is usually a DC signal and is added to the input or output of the system using a bias circuit.
The Velocity Signal
The velocity signal is a signal that is used to measure the speed of a system's response. It is usually a derivative of the output signal and is used to determine the system's stability and response time. The velocity signal is essential in determining the corrective action that needs to be taken to reduce the error and achieve the desired output response.
Conclusion
In conclusion, the actuating signal is the difference between the output response and the reference signal in a control system. It is used to determine the corrective action that needs to be taken to reduce the error and achieve the desired output response. The bias signal is a constant signal that is added to the input or output of a system to offset the system's response. The velocity signal is a signal that is used to measure the speed of a system's response and is essential in determining the corrective action needed to reduce the error and achieve the desired output response.
In a control system, the output response is compared with the reference signal to determine the error. The difference between the two signals is known as the actuating signal. This signal is crucial in determining the corrective action that needs to be taken to reduce the error and achieve the desired output response.
The actuating signal is usually a voltage or current signal that is used to control the system's input or output. It is generated by the controller and is used to activate the actuator, which in turn, adjusts the system's output.
The actuating signal is an essential component of a control system as it determines the corrective action that needs to be taken to reduce the error and achieve the desired output response. In the absence of an actuating signal, the control system would not be able to correct the error and achieve the desired output.
The Bias Signal
The bias signal is a constant signal that is added to the input or output of a system. It is used to offset the system's response and to ensure that it operates within a specific range. The bias signal is usually a DC signal and is added to the input or output of the system using a bias circuit.
The Velocity Signal
The velocity signal is a signal that is used to measure the speed of a system's response. It is usually a derivative of the output signal and is used to determine the system's stability and response time. The velocity signal is essential in determining the corrective action that needs to be taken to reduce the error and achieve the desired output response.
Conclusion
In conclusion, the actuating signal is the difference between the output response and the reference signal in a control system. It is used to determine the corrective action that needs to be taken to reduce the error and achieve the desired output response. The bias signal is a constant signal that is added to the input or output of a system to offset the system's response. The velocity signal is a signal that is used to measure the speed of a system's response and is essential in determining the corrective action needed to reduce the error and achieve the desired output response.
The type of a system denotes the number of- a)zeros of infinity
- b)poles of origin
- c)poles of infinity
- d)zeros of origin
Correct answer is option 'B'. Can you explain this answer?
The type of a system denotes the number of
a)
zeros of infinity
b)
poles of origin
c)
poles of infinity
d)
zeros of origin
|
Rhea Dasgupta answered |
The type of a system denotes the no. of poles of origin.
Introduction of feedback to a system- a)increases the stability
- b)decreases the stability
- c)has no effect on stability
- d)none of the above
Correct answer is option 'D'. Can you explain this answer?
Introduction of feedback to a system
a)
increases the stability
b)
decreases the stability
c)
has no effect on stability
d)
none of the above
|
Pranjal Basu answered |
Introduction of feed back to a system will increase the stability if negative feedback is introduced while it will reduce the stability if positive feedback is introduced.
In open loop control systems, the control action is independent of the desired________.- a)Error detector
- b)Input signal
- c)Output signal
- d)Actuating signal
Correct answer is option 'C'. Can you explain this answer?
In open loop control systems, the control action is independent of the desired________.
a)
Error detector
b)
Input signal
c)
Output signal
d)
Actuating signal
|
Lekha Malhotra answered |
Understanding Open Loop Control Systems
Open loop control systems are characterized by their operational independence from the output. This means that the control action is not influenced by the output signal, which distinguishes them from closed loop systems.
Key Features of Open Loop Control Systems:
- Independence from Output:
- In an open loop system, the control action is determined solely by the input signal and does not adjust based on the output signal's actual performance. This lack of feedback means that the system does not correct itself if the output deviates from the desired result.
- No Error Detection:
- Unlike closed loop systems, open loop systems do not have an error detector to measure the difference between the desired output and the actual output. Thus, they cannot make real-time adjustments.
- Control Action Based on Input:
- The system relies on predetermined inputs to generate a control action. For example, a washing machine set to a specific cycle will operate based on that cycle's parameters without considering the cleanliness of the clothes.
Examples of Open Loop Control Systems:
- Electric Fans:
- A fan operates at a set speed regardless of the room temperature or airflow.
- Toasters:
- A toaster heats bread for a fixed duration, irrespective of the desired toastiness.
Conclusion:
In summary, the correct answer to the question is option 'C'—the control action in open loop systems is indeed independent of the desired output signal. This trait leads to simplicity in design and operation but also limits the system's adaptability and accuracy.
Open loop control systems are characterized by their operational independence from the output. This means that the control action is not influenced by the output signal, which distinguishes them from closed loop systems.
Key Features of Open Loop Control Systems:
- Independence from Output:
- In an open loop system, the control action is determined solely by the input signal and does not adjust based on the output signal's actual performance. This lack of feedback means that the system does not correct itself if the output deviates from the desired result.
- No Error Detection:
- Unlike closed loop systems, open loop systems do not have an error detector to measure the difference between the desired output and the actual output. Thus, they cannot make real-time adjustments.
- Control Action Based on Input:
- The system relies on predetermined inputs to generate a control action. For example, a washing machine set to a specific cycle will operate based on that cycle's parameters without considering the cleanliness of the clothes.
Examples of Open Loop Control Systems:
- Electric Fans:
- A fan operates at a set speed regardless of the room temperature or airflow.
- Toasters:
- A toaster heats bread for a fixed duration, irrespective of the desired toastiness.
Conclusion:
In summary, the correct answer to the question is option 'C'—the control action in open loop systems is indeed independent of the desired output signal. This trait leads to simplicity in design and operation but also limits the system's adaptability and accuracy.
As compared to an open loop system, a closed loop system is:- a)More accurate as well as more stable
- b)Less accurate but more stable
- c)More stable but less accurate
- d)Less accurate as well as less stable
Correct answer is option 'A'. Can you explain this answer?
As compared to an open loop system, a closed loop system is:
a)
More accurate as well as more stable
b)
Less accurate but more stable
c)
More stable but less accurate
d)
Less accurate as well as less stable
|
Vihaan Gupta answered |
Understanding Open Loop vs Closed Loop Systems
Open loop and closed loop systems are fundamental concepts in control engineering. Here's a breakdown of their characteristics and the reasons why closed loop systems are generally more accurate and stable.
Definition of Systems
- Open Loop System: Operates without feedback. The output is not measured or compared to the input. Examples include simple devices like toasters and washing machines, where the operation is predetermined.
- Closed Loop System: Utilizes feedback to compare the actual output with the desired output. Adjustments are made based on this comparison, ensuring the system can correct errors.
Why Closed Loop Systems are More Accurate
- Feedback Mechanism: Closed loop systems continuously monitor the output and adjust inputs to minimize errors. This feedback loop allows for real-time corrections, enhancing precision.
- Adaptability: They can adapt to changing conditions and disturbances, maintaining performance over time.
Why Closed Loop Systems are More Stable
- Error Correction: The feedback in closed loop systems helps stabilize the output. If there's any deviation from the desired performance, the system can self-correct to return to stability.
- Reduced Sensitivity to Disturbances: Closed loop systems can handle external disturbances more effectively, maintaining stability under varying conditions.
Conclusion
In summary, closed loop systems are indeed more accurate and stable due to their inherent feedback mechanisms. This allows for real-time adjustments, making them preferable for applications requiring precision and reliability.
Open loop and closed loop systems are fundamental concepts in control engineering. Here's a breakdown of their characteristics and the reasons why closed loop systems are generally more accurate and stable.
Definition of Systems
- Open Loop System: Operates without feedback. The output is not measured or compared to the input. Examples include simple devices like toasters and washing machines, where the operation is predetermined.
- Closed Loop System: Utilizes feedback to compare the actual output with the desired output. Adjustments are made based on this comparison, ensuring the system can correct errors.
Why Closed Loop Systems are More Accurate
- Feedback Mechanism: Closed loop systems continuously monitor the output and adjust inputs to minimize errors. This feedback loop allows for real-time corrections, enhancing precision.
- Adaptability: They can adapt to changing conditions and disturbances, maintaining performance over time.
Why Closed Loop Systems are More Stable
- Error Correction: The feedback in closed loop systems helps stabilize the output. If there's any deviation from the desired performance, the system can self-correct to return to stability.
- Reduced Sensitivity to Disturbances: Closed loop systems can handle external disturbances more effectively, maintaining stability under varying conditions.
Conclusion
In summary, closed loop systems are indeed more accurate and stable due to their inherent feedback mechanisms. This allows for real-time adjustments, making them preferable for applications requiring precision and reliability.
Which of the following is not true regarding an open loop control system?- a)Highly affected by non-linearities.
- b)Open loop systems are inaccurate.
- c)These are not reliable.
- d)The effect of parameter variation and internal noise is less.
Correct answer is option 'D'. Can you explain this answer?
Which of the following is not true regarding an open loop control system?
a)
Highly affected by non-linearities.
b)
Open loop systems are inaccurate.
c)
These are not reliable.
d)
The effect of parameter variation and internal noise is less.
|
Rahul Banerjee answered |
The effect of parameter variation and internal noise is more in an open loop system.
Consider the following statements regarding the properties of transfer function:
1. The transfer function is independent of the input of the system.
2. The transfer function is defined for linear time- variant system.
3. The transfer function of a continuous-data system is expressed only as a function of the complex variable s.
4. All the initial conditions are not necessarily set to zero for finding the transfer function of a given system.Q. Which of the above statements is/are not true?- a)1, 3 and 4 only
- b)2, 3 and 4 only
- c)1 and 3 only
- d)All of the above
Correct answer is option 'D'. Can you explain this answer?
Consider the following statements regarding the properties of transfer function:
1. The transfer function is independent of the input of the system.
2. The transfer function is defined for linear time- variant system.
3. The transfer function of a continuous-data system is expressed only as a function of the complex variable s.
4. All the initial conditions are not necessarily set to zero for finding the transfer function of a given system.
1. The transfer function is independent of the input of the system.
2. The transfer function is defined for linear time- variant system.
3. The transfer function of a continuous-data system is expressed only as a function of the complex variable s.
4. All the initial conditions are not necessarily set to zero for finding the transfer function of a given system.
Q. Which of the above statements is/are not true?
a)
1, 3 and 4 only
b)
2, 3 and 4 only
c)
1 and 3 only
d)
All of the above
|
Sanskriti Datta answered |
Correct Answer :- D
Explanation : The properties of transfer function are given below:
1) The ratio of Laplace transform of output to Laplace transform of input assuming all initial conditions to be zero.
2) The transfer function of a system is the Laplace transform of its impulse response under assumption of zero initial conditions.
3) Replacing ‘s’ variable with linear operation D = d/dt in transfer function of a system, the differential equation of the system can be obtained.
4) The transfer function of a system does not depend on the inputs to the system.
5) The system poles and zeros can be determined from its transfer function.
The transfer function of given system is:
- a)
- b)
- c)
- d)
Correct answer is option 'A'. Can you explain this answer?
The transfer function of given system is:
a)
b)
c)
d)
|
|
Sarita Yadav answered |
The signal flow graph given below.
The transfer function=
=
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