Statement (I) : A monostable multi-vibrator, when switched on remains in a quasi stable state. Statement (II) : Quasi stable state duration is decided by charging time of capacitor. 

Statement (I) : A monostable multi-vibrator, when switched on remains in a quasi stable state. Statement (II) : Quasi stable state duration is decided by charging time of capacitor.  Correct Answer Statement (I) is false but Statement (II) is true

The monostable multivibrator has one stable state and one quasi-stable state. The quasi=stable state exists on;y for a finite period of time depending on the time constant RC or charging of the capacitor. In the monostable multivibrator, a trigger pulse has to be applied to induce a transition from one stable state to quasi-stable state. However, a quasi-stable state does not require any trigger pulse to return to the stable state.

T = 0.69RC

Where T is the time duration after which the monostable multivibrator returns to stable from Quasi-state.

Hence, Statement (I) is false but Statement (II) is true

Monostable multivibrator:

  • The Monostable Multivibrator circuit has only ONE stable state making it a “one-shot” pulse generator
  • Monostable multivibrators can consider as triggered pulse generators
  • It is used as delay and timing circuits
  • It is used for the generation of clock pulse
  • It is used for ​the regeneration of distorted waves
  • It is also used in analog systems to control an output signal frequency

Note:

Bistable Multivibrator is used in memory and timing circuits such as flip-flops, counter (For counting purpose)

Astable Multivibrator is used as a square wave frequency generator. and applications like pulse position modulation, frequency modulation.

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