6. Consider the following statements regarding timedomain analysis of a control system :
   1. Derivative control improves system’s transient performance
   2. I ntegral control does not improve system’s steady state performance
   3. I ntegral control can convert a second order system into a third order system
   Of these statements
   

1. 1. 1 and 2 are correct

   
   
   

   2. 1 and 3 are correct

   
   
   

   3. 2 and 3 are correct

   
   
   

   4. 1, 2 and 3 are correct

   
   
   

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1. View Hint View Answer Discuss in Forum

   For same K_V, the natural frequency ω_n remains unchanged in derivative control while damping is increased.
   Thus it improves the transient response.
   Integral compensator introduces a term 1/s, thus changes second order to third order.

   Correct Option: B

   For same K_V, the natural frequency ω_n remains unchanged in derivative control while damping is increased.
   Thus it improves the transient response.
   Integral compensator introduces a term 1/s, thus changes second order to third order.

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7. The position and velocity error coefficients for the system of transfer function
   

   G(s) =	50
   	(1 + 0.1s)(1 + 2s)

   
   respectively are

1. 1. zero and zero

   
   
   

   2. zero and infinity

   
   
   

   3. 50 and zero

   
   
   

   4. 50 and infinity

   
   
   

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1. View Hint View Answer Discuss in Forum

   

   Correct Option: C

   

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8. For the unity feedback system shown below, the steady state error, when the input is
   

   R =	3	-	1	+	1	, would be
   	s		s2		2s3

   
   

1. 1. 1

      4

      
      

   
   
   

   2. 0
      

   
   
   

   3. ∞
      

   
   
   

   4. 1

      2

   
   
   

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1. View Hint View Answer Discuss in Forum

   Steady state error,
   

   Correct Option: A

   Steady state error,
   

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9. In the derivative error compensation, damping
   

1. 1. decreases and settling time decreases

   
   
   

   2. increases and settling time increases

   
   
   

   3. decreases and settling time increases

   
   
   

   4. increases and settling time decreases

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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10. For a feedback control system of type 2, the steady state error for a ramp input is
    

1. 1. infinite

   
   
   

   2. constant

   
   
   

   3. zero

   
   
   

   4. indeterminate

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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