After research of this science I have found that the thermistor is made from a semi-conductible material which we have been told is an NTC ( negative temperature coefficient). In this case I believe that as the temperature increases the resistance will decrease as more electrons are freed and the material becomes a better conductor. The graph produced at the end of this experiment should therefore look like this: Preliminary Experiment Before the main experiment is carried out a preliminary experiment is needed to clarify several problems such as equipment choices and temperature ranges.
Also I have to find the time it takes to complete a trial of the experiment so I can work out how many readings it is possible to take in the given time. Method I need to set up the experiment in the way (shown later) I had pre-determined which included both an ammeter and a voltmeter, first preparing the pot by wrapping foam round it for insulation. I will put 3 layers of the foam on attached with elastic and a layer (cut in a circle) on the bottom after deciding that the time needed for each trial did not require masses of insulation.
I will then make the decision of whether to just the voltmeter and keep the ammeter at a constant by varying the voltage and using the variable resistor or whether to keep the ammeter independent and record both sets of data. I will also need to find out the hottest temperature of the boiling water and therefore determine the range of temperatures over which data will be collected. Also the number of recordings will have to be decided on depending on the time it takes to test at one temperature (of course certain other readings will have to be made if there is a large gap between the results).
The last decision to make is the accuracy of my results. When the equipment is set up the water will have to be put in the pot, boiling for the hot temperatures and ice for below temperatures. Then it is stirred and adjusted to the temperature needed. The thermistor is then put in the pot and given a minute or so to adjust to the temperature (the water periodically will need stirring to retain its temperature). A reading is then taken and recorded.