MCQs on Control system Part-1

Control System

1. In open loop control system_____.

a) Output is independent of control input

b) Output is dependent of control input

c) Only system parameters have effect on the control output

d) None of the above

2. A relay is used to______.

a) Break the fault current

b) Sense the fault

c) Sense the fault and direct to trip the circuit breaker

d) All of these

3. The primary function of a fuse is to_____.

a) Open the circuit

b) Protect the appliance

c) Protect the line

d) Prevent excessive currents from flow through the circuit

4. Anode of an operational SCR is as_______.

a) Always positive w.r.t. cathode

b) Always negative w.r.t. anode

c) Always positive w.r.t. anode

d) Always negative w.r.t. cathode

5. Number of PN junction in an SCR is______.

a) Two

b) Three

c) Four

d) Five

6. In rectifiers, load current flow is________.

a) Unidirectional

b) Bidirectional

c) Either (a) or(b)

d) Non-directional

7. Applications of Cyclo-converters include______.

a) speed control of ac drives

b) induction heating

c) static VAR compensation

d) all of the mentioned

8. Inverter converts______.

a) dc power to dc power

b) dc power to ac power

c) ac power to ac power

d) ac power to dc power

9. A step - down choppers can be used in______.

a) Electric traction

b) Electric vehicles

c) Machine tools

d) All of these

10. The rate of heat produced by dielectric heating is increased by______.

a) Increasing frequency and voltage supply

b) Increasing frequency and decreasing voltage supply

c) Decreasing frequency and voltage supply

d) Decreasing frequency and increasing voltage supply

11. The initial response when the output is not equal to the input is called______.

a) Transient response

b) Error response

c) Dynamic response

d) Either of the above

12. A control system working under unknown random actions is called______.

a) computer control system

b) digital data system

c) stochastic control system

d) adaptive control system

13. An automatic toaster is a ______ loop control system.

a) open

b) closed

c) partially closed

d) any of the above

14. Any externally introduced signal affecting the controlled output is called a________.

a) feedback

b) stimulus

c) signal

d) gain control

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

a) Servomechanism

b) Feedback

c) Output pattern

d) Input pattern

16. ________ is a part of the human temperature control system.

a) Digestive system

b) Perspiration system

c) Ear

d) Leg movement

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

a) Brain

b) Hands

c) Legs

d) Eyes

18.______ is a closed loop system.

a) Auto-pilot for an aircraft

b) Direct current generator

c) Car starter

d) Electric switch

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

a) Vernistats

b) Microsyns

c) Resolvers

d) Any of the above

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

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

21.________ increases the steady state accuracy.

a) Integrator

b) Differentiator

c) Phase lead compensator

d) Phase lag compensator

22. A.C. servomotor resembles______.

a) two phase induction motor

b) Three phase induction motor

c) direct current series motor

d) universal motor

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

a) Band width

b) Overall gain

c) Distortion

d) Instability

24. Regenerative feedback implies feedback with_______.

a) oscillations

b) step input

c) negative sign

d) positive sign

25. The output of a feedback control system must be a function of______.

a) reference and output

b) reference and input

c) input and feedback signal

d) output and feedback signal