Answer:
A good example of a negative feedback control mechanism is the thermostat found in most electronic ovens. The oven system consists of two main parts, the heating element(which heats the oven) and a thermostat(which detects temperature within the oven). The system operated thus:
1.A certain temperature is selected on the oven.
2.If the thermostat reads a lower temperature than selected inside the oventhe heating element is switched on and the oven begins to heat up
3.Once the Temperature is equal to or greater than the desired temperature selected, the themostat will switch the heating element off and the oven will begin to cool down.
4.The oven will continue to cool down until the thermostat detects a temperature lower than that desire and turns the element back on again.
This is type of feedback is used to achieve a certain level of a specific variable and comes in many different forms, a few other examples are central heating systems, automatic Louvre controls etc. The advantage of this type of control is that it is simple to employ in a variety of situations and the components are fairly cheap and simple. One drawback of this form of control is that it causes lag which results (taking the oven as an example) in the delay between the heating element switching off and the oven cooling and between the oven cooling and the thermostat detecting a low temperature.
When you get too hot you start to sweat to cool off, that is a negative feedback mechanism.