Question 1

Difference equation model results in:
A)sampled-data systems
B)numerical analysis of continuous time systems
C)continuous time feedback systems
D)both a and b

Accepted Answer

Difference equation models are used in the analysis of sampled-data systems, where the continuous signal is sampled at discrete intervals, and in numerical analysis to approximate the behavior of continuous-time systems. They do not directly model continuous-time feedback systems.

Question 2

For relative stability of the system which of the following is sufficient?
A)gain margin
B)phase margin
C)both a and b
D)magnitude

Accepted Answer

Gain margin and phase margin both are measures of the system's relative stability, indicating how much the system's gain or phase can change before it becomes unstable.

Question 3

Stability of a system implies that :
A)small changes in the system input does not result in large change in system output
B)small changes in the system parameters does not result in large change in system output
C)small changes in the initial conditions does not result in large change in system output
D)small changes in the initial conditions result in large change in system output

Accepted Answer

Stability of a system means that small changes in the system input do not lead to large changes in the system output, ensuring predictable and controlled behavior.

Question 4

Linear mathematical model applies to :
A)linear systems
B)stable systems
C)unstable systems
D)all of the mentioned

Accepted Answer

The answer of Linear mathematical model applies to :
A)linear systems
B)stable...

Question 5

With feedback _____ reduces.
A)system stability
B)system gain
C)system stability and gain
D)damping

Accepted Answer

Feedback typically reduces system gain by feeding a portion of the output back into the system input, often resulting in a lower overall gain.

Question 6

Asymptotic stability is concerned with:
A)a system under influence of input
B)a system not under influence of input
C)a system under influence of output
D)a system not under influence of ou

Accepted Answer

Asymptotic stability refers to the behavior of a system when it is not under the influence of an external input. It is about the system's ability to return to a state of equilibrium after a disturbance when no external forces are acting on it.

Question 7

A linear time invariant system is stable if :
A)system in excited by the bounded input, the output is also bounded
B)in the absence of input output tends zero
C)both a and b
D)system in excited by the bounded input, the output is not bounded

Accepted Answer

A linear time-invariant (LTI) system is considered stable if it satisfies both conditions: when excited by a bounded input, the output remains bounded (A), and in the absence of any input, the output tends to zero (B). Both conditions are essential for defining the stability of LTI systems.

Question 8

If a system is given unbounded input then the system is:
A)stable
B)unstable
C)not defined
D)linear

Accepted Answer

The answer of If a system is given unbounded input...

Question 9

If the impulse response in absolutely integrable then the system is :
A)absolutely stable
B)unstable
C)linear
D)stable

Accepted Answer

If the impulse response is absolutely integrable, then the system is absolutely stable. This is because the impulse response is a measure of the system's response to an impulse input, and if the impulse response is absolutely integrable, then the system's response to any input will be bounded.

Question 10

If root of the characteristic equation has positive real part the system is :
A)stable
B)unstable
C)marginally stable
D)linear

Accepted Answer

A system is considered unstable if the root of its characteristic equation has a positive real part, as this implies that the system's response grows without bound over time.

Question 11

The use of sampled data control system are:
A)for using analog components as the part of the control loop
B)for time division of control components
C)whenever a transmission channel forms a part of closed loop
D)none of the mentioned

Accepted Answer

Sampled data control systems are used when a transmission channel forms a part of the closed loop, as they allow for the handling of discrete signals in systems where data is transmitted in samples.

Question 12

Jury's test determines whether the roots of a polynomial lie:
A)close to unit circle
B)within the unit circle
C)outside the unit circle
D)on the unit circle

Accepted Answer

Jury's test is a stability criterion used in control theory to determine if all the roots of a polynomial lie within the unit circle in the complex plane, which indicates system stability.

Question 13

The transformation technique in which there is one to one mapping from s-domain to z-domain is
A)approximation of derivatives
B)impulse invariance method
C)bilinear transformation method
D)backward difference for the derivative

Accepted Answer

The bilinear transformation method involves a one-to-one mapping from the s-domain to the z-domain, ensuring a direct correspondence between the analog and digital filter characteristics. This method is widely used in digital signal processing for designing digital filters based on analog prototypes.

Question 14

Parallel form of realisation is done in
A)high speed filtering applications
B)low speed filtering applications
C)both a and b
D)none of the above

Accepted Answer

Parallel form of realization is typically used in high speed filtering applications to achieve faster processing by executing multiple operations simultaneously.

Question 15

In cascade form of realization, how many bits should be used to represent the FIR filter coefficients in order to avoid the quantization effect on filter coefficients?
A)5 to 10
B)12 to 14
C)20 to 24
D)28 to 40

Accepted Answer

The quantization effect on filter coefficients can be avoided by using a sufficient number of bits to represent the coefficients. In cascade form of realization, the number of bits required depends on the number of stages in the cascade. For a typical cascade filter with 10-20 stages, 12-14 bits are usually sufficient to avoid the quantization effect.

Question 16

How is the sampling rate conversion achieved by factor I/D?
A)by increase in the sampling rate with (i)
B)by filtering the sequence to remove unwanted images of spectra of original signal
C)by decimation of filtered signal with factor d
D)all of above

Accepted Answer

Sampling rate conversion by a factor of I/D involves increasing the sampling rate by I (interpolation), filtering the sequence to remove unwanted spectral images, and then decimating the filtered signal by a factor of D. This process ensures that the converted signal maintains the desired characteristics while adjusting the sampling rate.

Question 17

In the cascaded form of realisation, the polynomials are factored into
A)product of 1st-order and 2nd-order polynomials
B)product of 2nd-order and 3rd-order polynomials
C)sum of 1st-order and 2nd-order polynomials
D)sum of 2nd-order and 3rd-order polynomials

Accepted Answer

In the cascaded form of realization, the approach involves breaking down the polynomials into a product of first-order and second-order polynomials. This method simplifies the design and analysis of filters or systems by dealing with lower-order systems.

Question 18

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

Accepted Answer

A system with a zero in the right half of the s-plane (positive real value) is called a non-minimum phase system because its phase decreases with increasing frequency, which is opposite to the behavior of a system with all poles and zeros in the left half of the s-plane.

Question 19

Consider the function F (s)= 5/s(s^2+3s+2), the initial value of f(t) is:
A)5
B)5/2
C)5/3
D)0

Accepted Answer

The initial value theorem states that if $F(s) = \mathcal{L}\{f(t)\}$ and the limit as $s$ approaches infinity of $sF(s)$ exists, then the initial value of $f(t)$ as $t$ approaches 0 is given by $\lim_{s \to \infty} sF(s)$. For $F(s) = \frac{5}{s(s^2+3s+2)}$, $\lim_{s \to \infty} s \cdot \frac{5}{s(s^2+3s+2)} = 0$, indicating the initial value of $f(t)$ is 0.

Question 20

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

Accepted Answer

The answer of In a closed loop for which the...

Quiz 2: Stability and Realization of Linear Systems With Feedback and Sampling

Difference equation model results in:

For relative stability of the system which of the following is sufficient?

Stability of a system implies that :

Linear mathematical model applies to :

With feedback _____ reduces.

Asymptotic stability is concerned with:

A linear time invariant system is stable if :

If a system is given unbounded input then the system is:

If the impulse response in absolutely integrable then the system is :

If root of the characteristic equation has positive real part the system is :

The use of sampled data control system are:

Jury's test determines whether the roots of a polynomial lie:

The transformation technique in which there is one to one mapping from s-domain to z-domain is

Parallel form of realisation is done in

In cascade form of realization, how many bits should be used to represent the FIR filter coefficients in order to avoid the quantization effect on filter coefficients?

How is the sampling rate conversion achieved by factor I/D?

In the cascaded form of realisation, the polynomials are factored into

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

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

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