In a system with a positive feedback, a component of response to the stimulus is fed back as stimulus. The component that is fed back is decided by a feedback system. Because it is a positive feedback, this component is in tandem with the usual stimulus. This phenomenon results in an stimulus of enhanced magnitude. The regular stimulus when combined additively with this component that is fed back creates an enhanced input to this system thereby increasing the effective magnitude of the response which in turn increases the fed back component. This can go on forever, continuously increasing the strength of the response of the system. Now the system might not be able to cope with this high magnitude of stimulus or response, sometimes it could be the excess response or it could be the excess stimulus, that causes the system to breakdown or stop responding beyond its acceptable limit of either magnitudes making the system saturated.
Sometimes the component that is fed back might not be contain all the components of the given stimulus, it could be just one component of the stimulus that could be fed back to be additively combined with stimulus. Now this component that will be fed back is entirely a property of the feedback. If the stimulus does not contain this particular component that the feedback system is sensitive to, the feedback system is practically useless. But if the mentioned component is a part of stimulus then this one component will get contribute the most to the response. Now if a response of a certain magnitude is being generated by the system, we may safely remove the stimulus and the response will be available, even without the stimulus. This this fed back component becomes the natural response of the system. Finding the natural response of a system is easy, one has to give it a small stimulus with all possible components for a short period, the system will respond with its natural response. Kicking a machine when it stops could just make it work as it put it up to its natural response once again. Like defibrillator.
Sometimes the component that is fed back might not be contain all the components of the given stimulus, it could be just one component of the stimulus that could be fed back to be additively combined with stimulus. Now this component that will be fed back is entirely a property of the feedback. If the stimulus does not contain this particular component that the feedback system is sensitive to, the feedback system is practically useless. But if the mentioned component is a part of stimulus then this one component will get contribute the most to the response. Now if a response of a certain magnitude is being generated by the system, we may safely remove the stimulus and the response will be available, even without the stimulus. This this fed back component becomes the natural response of the system. Finding the natural response of a system is easy, one has to give it a small stimulus with all possible components for a short period, the system will respond with its natural response. Kicking a machine when it stops could just make it work as it put it up to its natural response once again. Like defibrillator.
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