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Right ANSWER is (b) 20

Best explanation: The characteristic EQUATION is considered and the values of G and W are CALCULATED and further the VALUE of k can be calculated.

Right option is (a) True

Explanation: RISE time, peak time, settling time and maximum peak OVERSHOOT are the prime factors of the time domain analysis and they must be specified in a consistent MANNER but they are mutually dependent.

The CORRECT option is (B) 0.5

To explain I WOULD say: T(s) = 1/(s^2+2s+4)

G = 0.5.

Right OPTION is (b) Observability

The explanation: Observability and controllability are the two methods to check the output response CHARACTERISTICS and observability in CONTROL engineering implies an ability to measure the state by TAKING measurements at output.

Correct ANSWER is (d) All of the mentioned

Best explanation: Valves may be CONTROLLED manually, electrically, MECHANICALLY, pneumatically, hydraulically or by combination of these METHODS and they are used to control the flow of liquid by onstructing the flow.

The correct ANSWER is (d) Both b and c

For explanation I would say: A robot may not injure a HUMAN being or through in ACTION, ALLOW human being to be harmed.

The correct option is (b) It produces OFFSET

Best explanation: Main DISADVANTAGE of proportional CONTROLLER is produces the permanent error is CALLED offset error.

Correct option is (B) Speed of response

Best explanation: Speed of response is the speed at which the response takes the final VALUE and this is determined by damping FACTOR which REDUCES the oscillations and peak overshoot as the peak is less then the speed of response will be more.

The CORRECT OPTION is (d) All of the mentioned

Easy explanation: The sensitivity depends UPON the frequency, loop gain and forward gain of the CLOSED loop control SYSTEM.

The correct OPTION is (b) OUTPUT equations

To elaborate: Output Equations constitute the state MODEL of a SYSTEM in addition to state equations and for the complete state model mainly input model, output model and state models are required.

The correct answer is (c) Minimum PHASE system

To elaborate: Minimum phase system is defined as the perfect system with zeroes greater than poles and also the zeroes and poles lying on the LEFT half of the s plane entirely.

Right option is (c) Reciprocating PUMP

The best I can explain: Reciprocating Pump is a type of POSITIVE PUMPS which includes the piston pump, plunger pump and diaphragm pump and provides the FLOW of fluid in the cylinder by BACK and forth motion of the piston.

The correct option is (a) Both A and R true and R is correct explanation of A

Explanation: An off-off CONTROLLER is the INITIAL version of the PROPORTIONAL controller and it gives the self-sustained oscillations and location of poles on the imaginary AXIS gives the self-sustained oscillations.

The correct ANSWER is (a) STEADY state error

For explanation I WOULD say: Steady state accuracy entirely DEPENDS on the accuracy of steady state which is determined by steady state error which is the difference between the FINAL output and desired output.

The correct answer is (d) All of the mentioned

The best EXPLANATION: Steady STATE error, damping FACTOR and settling times are the SPECIFICATIONS are NEEDED to control the system’s stability and speed of response.

Right OPTION is (B) False

The BEST explanation: A perfect impulse signal has infinite value at zero but mathematically only a small PULSE is taken with finite limits.

Right option is (a) 0.2, 0.33 and 0.5

The explanation is: Output RESPONSE so calculated is the inverse Laplace transform of the input and impulse response and HENCE converting the resultant form in the TIME CONSTANT form time constant can be DIRECTLY determined.

Correct option is (B) 4 sec

The best I can explain: G(s) =100/(s+1) (s+100)

Taking the DOMINANT POLE consideration,

S=-100 pole is not taken.

G(s)= 100/s+1

Now it is first ORDER system, ts=4T=4 sec.

Right answer is (d) All of the mentioned

For EXPLANATION I WOULD SAY: STANDARD test signals are impulse, ramp and unit STEP all of the above to test the dynamic behavior of the control system.

The correct OPTION is (a) STATE SPACE analysis

The best I can EXPLAIN: State space analysis is different from the transfer function approach as this can be used for the analysis of multiple input and multiple OUTPUT system.

The correct answer is (b) 2

For explanation I WOULD say: The number of states REQUIRED to DESCRIBE a NETWORK is equal to the number of energy STORING elements in the electrical network.

Right OPTION is (a) Both assertion and reason are TRUE and R is correct explanation of A

The explanation is: Feedback compensation is preferred to series compensation or CASCADE compensation because:

In a feedback compensator energy transfer is from HIGHER to a lower one thereby OBVIATING the need for the feedback amplification.

Correct answer is (B) Potentiometer

Easy EXPLANATION: Potentiometer among all the options cannot be the final control element as this is responsible to GET the output in measurable FORM.

Correct choice is (C) 4s

For EXPLANATION: C(s)/R(s) = 2/s+1

R(s) = 1/s (STEP INPUT)

C(s) = 2/s(s+1)

c(t) = 2[1-e^-t]

1.96 = 2[1-e^-T]

T= 4SEC.

Correct choice is (b) 2

To explain: Routh-Hurwitz criterion is USED to calculate the STABILITY of the SYSTEM by checking the sign changes of the first row and from Routh-Hurwitz criterion maximum value of K = 6 ESS = A/Kv for type-1 system and A = 6then for Kv = K/2, ess = 2.

The correct choice is (a) True

Explanation: As the TYPE of the system becomes higher more STEADY state errors are ELIMINATED.

Correct answer is (d) DECAYS quickly

To elaborate: The transient RESPONSE of the system is IMPROVED with the HELP of the feedback and hence the transient response decays SLOWLY.

Right answer is (d) 0.25

To explain: The integrator is similar to the phase lag SYSTEMS and it is used to reduce or eleminate the steady state error and when it is cascaded with the RAMP input hence the ACCELERATION error CONSTANT is calculated which is equal to 0.25.

Right OPTION is (a) MAXIMUM peak overshoot

For explanation: Maximum peak overshoot is the normalized difference between the TIME RESPONSE peak and steady state output.

The CORRECT choice is (c) High POSITIVE correcting torque

Easiest explanation: Large overshoot refers to the maximum peak in the RESPONSE of the closed loop SYSTEM and this is MAINLY due to the high positive correcting torque.

The correct CHOICE is (d) Parallel DECOMPOSITION

For EXPLANATION: The state equation from transfer function by parallel decomposition in the PHASE CANONICAL form.

The correct ANSWER is (B) Joint

To explain: A joint is CONNECTION between parts or links in a ROBOT that allow motion. It has translator and ROTATORY motion.

Correct answer is (a) Both A and R are true and R is not correct EXPLANATION of A.

The explanation: Valves is defined as any device by which the FLOW of LIQUID can be controlled by OBSTRUCTING the flow of liquid and is all but impossible to design a practical fluid power system without some means of controlling the volume and pressure of the fluid.

Right option is (d) RS and SSE are reduced

To elaborate: INTEGRAL CONTROLLER acts like a low pass filter. It reduces the stability as well as steady state error.

Correct ANSWER is (a) True

To explain I would SAY: These are more DIFFICULT to STABILIZE and DYNAMIC errors are much larger.

Correct answer is (c) No oscillations

The explanation: complex conjugate (non-multiple): OSCILLATORY (sustained oscillations)

Complex conjugate (multiple): UNSTABLE (GROWING oscillations).

The correct option is (d) 1/t2

For EXPLANATION I WOULD SAY: G(s) = K/s+a

C(s) =K/(s+a) SINCE R(s) =1

C(t) =Ke^^-at

T=1/a

C(t) =0.37K

T= t2=1/a.

Right choice is (d) 1/(s+2)

To EXPLAIN I would say: Taking Laplace transform of the equation X(s) = 2U(s)/(s+2)

Then Y(s)/U(s) =1/(s+2).

The correct choice is (B) Error signal

To EXPLAIN I would say: Input to the controller is ALWAYS the parameter of the system which is to be CONTROLLED that is the DESIRABLE value.