What is the purpose of a positive feedback mechanism?

Answer 1

In most devices, positive feeback is usually a bad thing, as it leads to instability...for example, the feet marching across the millenium bridge in London caused the bridge to oscillate and sway. this was because the movement of the bridge was being reinforced and amplified by the steps of the people using it.
Sometimes positive feedback is deliberately used to create instability (for example in an electronic tuned circuit frequency generator)

Negative feedback is widely used to reduce instability and as a control mechanism in electronic, electrical and even mechanical devices

Answer 2

Are you saying that you didn't ask the question correctly last time? The purpose is that you will know whether you asked your question correctly or not - so if you get the feedback that you expect, then the chances are that you asked the question correctly in the first place. If all you got was negative feedback ir answers that you did not expect, then it is because you did not ask the question correctly in the first place.

Answer 3

In biology, it is something like this - the body detects abnormal levels of a substance or a process in the body. This causes further change so that the levels of whatever it is move even further away from the normal.
For example, in the case of hypothermia - when the body temperature starts to fall under the normal of 37 degrees it causes the metabolic rat,e or level of respiration in cells, to drop.This means that the body produces even less heat and the circle continues.
The opposite is negative feedback control when the detection of abnormal levels leads to action being taken to bring it back to normal, or the presence of a substance (eg. a hormone) inhibiting the production of another.

Answer 4

Positive feedback is a bit like an on/off switch. For example, if a substrate is available, its presence switches on a response system, that is otherwise off in its absence. It is almost an energy saving mechanism.

Answer 5

I'm no expert but I beilieve in biology terms negative feedback is used by the body for regulating things mainly with hormones such as insulin or ADH (kidneys).

Positive feedback is generally bad in body terms as its unstable eg. if your core temperature increases above 106 celcius then your body will start producing even more heat and your body temperature will spiral out of control eventually destroying your proteins = not good.

Bit vague but hope that helps!

Answer 6

Positive feedback is a good thing.It lets you know that people AGREE with you on the subject that you are talking about.Negative feedback is when someone DISAGREES with you.

Answer 7

To create an equal or greater energy transfer. It would be pointless to run a device that produces nothing for your efforts. Like setting a fan on the back of your sailboat.

Answer 8

The purpose is that you know if you've done smth good and that you are appreciated!
It does good to your ego and raises your self esteem level! It is very important with children!Otherwise they won't develop a positive image of themselves.

Answer 9

Well put it this way, If you put al your time and effort into something and nobody ever told you how they found it, wouldn't you be upset?

You need positive feedback otherwise you never know how popular something was or if it worked.

Answer 10

It's to make you feel better about your poor physical or mental ability.