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===About Thermistors===
: 'NTC' '''thermistors''' decrease [[Electrical Resistance|resistance]] as the [[temperature]] increases.(NTC = Negative Temperature Coefficient.)
: A '''thermistor''' can be used to control the [[Electrical Current|current]] passing through a [[circuit]]. If the [[Potential Difference|potential difference]] is constant then the [[Electrical Current|current]] decreases as [[temperature]] decreases.
: A '''thermistor''' can be used to control the [[Potential Difference|potential difference]] of another [[Electrical Component|component]] in [[Series Circuit|series]] with it. If the [[temperature]] is decreased then the [[Potential Difference|potential difference]] across other [[Electrical Component|components]] will decrease.
: '''Thermistors''' can be used [[temperature]] sensors.
===IV Graph===
{| class="wikitable"
|[[File:IVGraphThermistor.png|center|400px]]
|}
====Description====
The [[IV Graph]] for an 'NTC' [[thermistor]] shows that:
*At a high [[temperature]] the [[Electrical Current|current]] increases rapidly with the [[Potential Difference|potential difference]]
*At a low [[temperature]] the [[Electrical Current|current]] increases slowly with the [[Potential Difference|potential difference]].
====Explanation====
: The [[Electrical Resistance|resistance]] of an 'NTC' [[thermistor]] increases as the [[temperature]] decreases.
====Obtaining the IV Graph====
{| class="wikitable"
|-
|[[File:ThermistorIVGraphCircuit.png|center|300px]]
| style="height:20px; width:300px; text-align:left;" |
#Connect an [[ammeter]] in [[Series Circuit|series]] with the [[thermistor]] to measure [[Electrical Current|current]] through the [[thermistor]].
#Connect a [[voltmeter]] in [[Parallel Circuit|parallel]] with the [[thermistor]] to measure the [[Potential Difference|potential difference]] across it.
#Use a [[Variable Resistor|variable resistor]] in [[Series Circuit|series]] with the [[thermistor]] to vary the [[Potential Difference|potential difference]] across the [[thermistor]].
#Place the [[thermistor]] in a [[beaker]] of cold [[water]] around 5°C.
#Start with a [[Potential Difference|potential difference]] of zero and increase the [[Potential Difference|potential difference]] by an interval of 0.2V up to 2V.
#Recording the reading on the [[voltmeter]] and [[ammeter]].
#Reverse the connections on the [[battery]] and repeat steps 4 and 5 to find the I-V relationship for negative [[Potential Difference|potential difference]] and [[Electrical Current|current]].
#Repeat steps 5-7 with the [[thermistor]] in a [[beaker]] of hot [[water]] around 40°C.
|}
===References===
====AQA====
:[https://www.amazon.co.uk/gp/product/0008158770/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0008158770&linkCode=as2&tag=nrjc-21&linkId=ec31595e720e1529e49876c3866fff6e ''Thermistor, pages 47, 52, 64-5, GCSE Physics; Student Book, Collins, AQA '']
:[https://www.amazon.co.uk/gp/product/1782945598/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945598&linkCode=as2&tag=nrjc-21&linkId=ad276ad49df77ab4b40ab4fd0fe10356 ''Thermistors, page 184, GCSE Combined Science; The Revision Guide, CGP, AQA '']
:[https://www.amazon.co.uk/gp/product/178294558X/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=178294558X&linkCode=as2&tag=nrjc-21&linkId=f0dfb66dafcb0c6e9449e7b1a4ae1ac452 ''Thermistors, page 27, GCSE Physics; The Revision Guide, CGP, AQA '']
:[https://www.amazon.co.uk/gp/product/019835939X/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=019835939X&linkCode=as2&tag=nrjc-21&linkId=57e96876985fc39b1a3d8a3e3dc238b6 ''Thermistors, page 57, GCSE Physics; Third Edition, Oxford University Press, AQA '']
:[https://www.amazon.co.uk/gp/product/1471851354/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851354&linkCode=as2&tag=nrjc-21&linkId=9012a0d354024419214fb3ad5ac44ba0 ''Thermistors, pages 293, 298-9, 316-17, GCSE Combined Science Trilogy 1, Hodder, AQA '']
:[https://www.amazon.co.uk/gp/product/1471851370/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851370&linkCode=as2&tag=nrjc-21&linkId=01c69b0ae058f809cf636033e6ba793e ''Thermistors, pages 43-4, 64-5, GCSE Physics, Hodder, AQA '']
:[https://www.amazon.co.uk/gp/product/1782946403/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782946403&linkCode=as2&tag=nrjc-21&linkId=32a0abb60dff015b15b50e9b1d7b4644 ''Thermistors, pages 60, 80, 81, GCSE Combined Science Trilogy; Physics, CGP, AQA '']
:[https://www.amazon.co.uk/gp/product/1782945970/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945970&linkCode=as2&tag=nrjc-21&linkId=a120d24dcc7cc7a58192069a3aafc1d2 ''Thermistors, pages 62, 82, 83, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA '']
====Edexcel====
:[https://www.amazon.co.uk/gp/product/1292120223/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1292120223&linkCode=as2&tag=nrjc-21&linkId=068ecf40278c32406a7f1c6e66751417 ''Thermistors, page 149, GCSE Physics, Pearson Edexcel '']
:[https://www.amazon.co.uk/gp/product/1782945741/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945741&linkCode=as2&tag=nrjc-21&linkId=30da4f2178da182547b62a7329d13b57 ''Thermistors, page 187, GCSE Combined Science; The Revision Guide, CGP, Edexcel '']
:[https://www.amazon.co.uk/gp/product/1782945733/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945733&linkCode=as2&tag=nrjc-21&linkId=2a2dbec9db6bf5766c0458d908fa0a52 ''Thermistors, page 74, GCSE Physics; The Revision Guide, CGP, Edexcel '']
:[https://www.amazon.co.uk/gp/product/1782948163/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782948163&linkCode=as2&tag=nrjc-21&linkId=0fdbfd5dd397d6e24a9dfb250f08587f ''Thermistors, pages 225, 226, 229, GCSE Physics, CGP, Edexcel '']
====OCR====
:[https://www.amazon.co.uk/gp/product/1782945695/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945695&linkCode=as2&tag=nrjc-21&linkId=ceafcc80bcad6b6754ee97a0c7ceea53 ''Thermistors, page 179, Gateway GCSE Combined Science; The Revision Guide, CGP, OCR '']
:[https://www.amazon.co.uk/gp/product/1782945687/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945687&linkCode=as2&tag=nrjc-21&linkId=9a598e52189317a20311d7a632747bc9 ''Thermistors, page 47, Gateway GCSE Physics; The Revision Guide, CGP, OCR '']
:[https://www.amazon.co.uk/gp/product/0198359837/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0198359837&linkCode=as2&tag=nrjc-21&linkId=3c4229e8b023b2b60768e7ea2307cc6f ''Thermistors, pages 108-109, 112, Gateway GCSE Physics, Oxford, OCR '']