Question 1

Which of the following statements is not necessarily correct for open control system ?

Accepted Answer

A)  Input command is the sole factor responsible for providing the control action
B)  Presence of non-linearities causes malfunctioning
C)  Less expensive
D)  Generally free from problems of non-linearities B

Question 2

In open loop system

Accepted Answer

A)  the control action depends on the size of the system
B)  the control action depends on system variables
C)  the control action depends on the input signal
D)  the control action is independent of the output D

Question 3

The initial response when the output is not equal to input is called

Accepted Answer

A)  Transient response
B)  Error response
C)  Dynamic response
D)  Either of the above A

Question 4

A closed loop system is distinguished from open loop system by which of the following ?

Accepted Answer

A)  Servomechanism
B)  Feedback
C)  Output pattern
D)  Input pattern

Question 5

A.C. servomotor resembles

Accepted Answer

A)  two phase induction motor
B)  Three phase induction motor
C)  direct current series motor
D)  universal motor

Question 6

has tendency to oscillate.

Accepted Answer

A)  Open loop system
B)  Closed loop system
C)  Both a)  and b) 
D)  Neither a)  nor b)

Question 7

A car is running at a constant speed of 50 km/h, which of the following is the feedback element for the driver ?

Accepted Answer

A)  Clutch
B)  Eyes
C)  Needle of the speedometer
D)  Steering wheel

Question 8

Which of the following is an open loop control system ?

Accepted Answer

A)  Field controlled D.C. motor
B)  Ward leonard control
C)  Metadyne
D)  Stroboscope

Question 9

Which of the following devices are commonly used as error detectors in instruments ?

Accepted Answer

A)  Vernistats
B)  Microsyns
C)  Resolvers
D)  Any of the above

Question 10

An automatic toaster is a ______ loop control system.

Accepted Answer

A)  open
B)  closed
C)  partially closed
D)  any of the above

Question 11

increases the steady state accuracy.

Accepted Answer

A)  Integrator
B)  Differentiator
C)  Phase lead compensator
D)  Phase lag compensator

Question 12

In closed loop control system, with positive value of feedback gain the overall gain of the system will

Accepted Answer

A)  decrease
B)  increase
C)  be unaffected
D)  any of the above

Question 13

A good control system has all the following features except

Accepted Answer

A)  good stability
B)  slow response
C)  good accuracy
D)  sufficient power handling capacity

Question 14

Which of the following should be done to make an unstable system stable ?

Accepted Answer

A)  The gain of the system should be decreased
B)  The gain of the system should be increased
C)  The number of poles to the loop transfer function should be increased
D)  The number of zeros to the loop transfer function should be increased

Question 15

As a result of introduction of negative feedback which of the following will not decrease ?

Accepted Answer

A)  Band width
B)  Overall gain
C)  Distortion
D)  Instability

Question 16

In an open loop control system

Accepted Answer

A)  Output is independent of control input
B)  Output is dependent on control input
C)  Only system parameters have effect on the control output
D)  None of the above

Question 17

By which of the following the control action is determined when a man walks along a path ?

Accepted Answer

A)  Brain
B)  Hands
C)  Legs
D)  Eyes

Question 18

is a part of the human temperature control system.

Accepted Answer

A)  Digestive system
B)  Perspiration system
C)  Ear
D)  Leg movement

Question 19

For open control system which of the following statements is incorrect ?

Accepted Answer

A)  Less expensive
B)  Recalibration is not required for maintaining the required quality of the output
C)  Construction is simple and maintenance easy
D)  Errors are caused by disturbances

Question 20

A control system in which the control action is somehow dependent on the output is known as

Accepted Answer

A)  Closed loop system
B)  Semiclosed loop system
C)  Open system
D)  None of the above

Exam 1: Control Systems and Feedback Loops: Understanding Open and Closed Loop Systems