61. The maximum phase shift that can be provided by a lead compensator with transfer function—
    

    Gc(s) =	1 + 6s
    	1 + 2s

    
    is—
    

1. 1. 15°
      

   
   
   

   2. 30°
      

   
   
   

   3. 45°
      

   
   
   

   4. 60°

   
   
   

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   Try yourself, same as 184.

   Correct Option: B

   Try yourself, same as 184.

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62. The polar plot of a type-1, 3-pole, open-loop system is shown in figure. The closedloop system is—
    

1. 1. always stable
      

   
   
   

   2. marginally stable
      

   
   
   

   3. unstable with one pole on the right half s-plane
      

   
   
   

   4. unstable with two poles on the right half s-plane

   
   
   

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   NA

   Correct Option: C

   NA

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63. The minimum number of states necessary to describe the network shown in the figure in a state variable form is—
    
    
    
    

1. 1. 2
      

   
   
   

   2. 3
      

   
   
   

   3. 4
      

   
   
   

   4. 6

   
   
   

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1. View Hint View Answer Discuss in Forum

   The minimum number of states necessary to describe a network is the number of independent energy storing elements in the network i.e., there are three elements in the given figure.

   
   

   Correct Option: B

   The minimum number of states necessary to describe a network is the number of independent energy storing elements in the network i.e., there are three elements in the given figure.

   
   

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64. Consider the vectors drawn form the poles and zeros at jω = 1 on the imaginary axis as shown in the given figure. The transfer function G (j1) is given by—
    
    
    
    

1. 1. 1/2 ∠0º
      

   
   
   

   2. 2.7 ∠ – 31º
      

   
   
   

   3. 2 ∠45º
      

   
   
   

   4. 2 ∠ – 67.4º

   
   
   

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   NA

   Correct Option: A

   NA

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65. The transfer function of a multi-input, multi-output system with the state-space representation is
    X · = AX + BU
    Y = CX + DU
    where X represents the present state, Y the output and U the input vector, will be given by—
    

1. 1. C (sl – A)^–1 B
      

   
   
   

   2. C (sl – A)^–1 B + D
      

   
   
   

   3. (sl – A)^–1 B + D
      

   
   
   

   4. C (sl – A)^–1 B

   
   
   

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1. View Hint View Answer Discuss in Forum

   Refer synopsis

   Correct Option: B

   Refer synopsis

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