21. A control system with excessive noise, is likely to suffer from

saturation in amplifying stages

loss of gain

vibrations

oscillations

22. is an open loop control system

Ward Leonard control

Field controlled D.C. motor

Stroboscope

Metadyne

23. .The output of a feedback control system must be a function of

reference and output

reference and input

input and feedback signal

output and feedback signal

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

The gain of the system should be decreased

The gain of the system should be increased

The number of poles to the loop transfer function should be increased

The number of zeros to the loop transfer function should be increased

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

Vernistats

Microsyns

Resolvers

Any of the above

26. The capacitance, in force-current analogy, is analogous to

momentum

velocity

displacement

mass

27. A controller, essentially, is a

sensor

clipper

comparator

amplifier

28. In a control system the output of the controller is given to

final control element

amplifier

comparator

sensor

29. In an automatic control system which of the following elements is not used ?

Error detector

Final control element

Sensor

Oscillator

30. In a stable control system backlash can cause which of the following ?

Underdamping

Overdamping

Poor stability at reduced values of open loop gain

Low-level oscillations

31. Mass, in force-voltage analogy, is analogous to

charge

current

inductance

resistance

32. In thermal-electrical analogy charge is considered analogous to

heat flow

reciprocal of heat flow

reciprocal of temperature

temperature

33. In force-voltage analogy, velocity is analogous to

current

charge

inductance

capacitance

34. The viscous friction co-efficient, in force-voltage analogy, is analogous to

charge

resistance

reciprocal of inductance

reciprocal of conductance

35. In liquid level and electrical system analogy, voltage is considered analogous to

head

liquid flow

liquid flow rate

none of the above

36. In electrical-pneumatic system analogy the current is considered analogous to

velocity

pressure

air flow

air flow rate

37. The temperature, under thermal and electrical system analogy, is considered analogous to

voltage

current

capacitance

charge

38. Equalizer is used for?

Filtering

Diminish distortion

All of the mentioned

None of the mentioned

39. Pulse shaping is done by which block or system?

Encoder

Baseband modulator

Pulse code modulator

Demodulator

40. What is the code rate?

k/n

n/k

All of the mentioned

None of the mentioned