• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month
  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  6. 6
  7. 7
  8. 8
  9. 9
  10. 10
  11. 11

Investigation in to what happens to the resistance of a thermistor as its temperature changes.

Extracts from this document...


Physics Coursework

Danielle Roots

Mr Small

Aim:  To investigate what happens to the resistance of a thermistor as its temperature changes.

What is a thermistor?

Is a resistor that changes in resistance with temperature.

“Its principle characteristic is that their electrical resistance changes in response to changes in their temperature.”


Symbol for a Thermistor:


Calculating resistance

Resistance in a circuit can be calculated using the levels of voltage and current in a wire or a single component.

The formula we use to measure resistance is:

RESISTANCE = VOLTAGE                        R = V

                      CURRENT                          I        

What is Current?

Current is the flow of electrons around an electric circuit.

It is measured in amps.  Current is measured in Amps.

1 amp = 1 coulomb per second

Per means divided by so current = charge






...read more.






Parallel Circuits    


 Series Circuits  

Only has one path for the charges to move along. Charges must move in "series" first going to one resistor then the next. If one of the items in the circuit is broken then no charge will move through the circuit because there is only one path. There is no alternative route.


In a series circuit voltage decreases as it travels around the circuit as the energy is being used up.  The current however will stay the same wherever it is measure around the circuit.  

The voltage used on each component add together to equal the reading from the voltage source.  Linking this to the equation   V = R


And the higher the voltage is going to be because the higher the resistance is because the current stays the same.

Ohms Law

Ohms law clearly states that

Resistance =  Voltage


...read more.


The same thermometer or at least the same type of thermometer I will use a liquid thermometer all the time because the readings I get could be different because of a thermometer being too or not accurate enough compared to other thermometers I used previously but in the same investigation.When I repeat results if I have time I want to wait until the thermistor cools down so this doesn’t affect the results because the heat of the thermistor could be different from that of the water and the results I get aren’t correct because the current and voltage results I am taking aren’t in relation to the temperature of the water because doing this experiment I am assuming he thermistor is the same temperature as the water.


  • I have to make sure none of the wires are in the water or are on something hot in case they burn etc.
  • When taking apparatus apart I need to make sure that I am careful I don’t burn myself
  • That I wear goggles in case of any fires or water boiling and bubbling into eyes.
  • That I don’t fill the water up too high on the beaker in case it splashes out and burns someone


Scientific Theory

...read more.

This student written piece of work is one of many that can be found in our AS and A Level Electrical & Thermal Physics section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Electrical & Thermal Physics essays

  1. To investigate how the temperature affects the resistance of a thermistor.

    thermistor this means that two variables are being changed and so the results wont be accurate. The current and potential difference (voltage) in affect the resistance in a thermistor because the greater the voltage the more energy the electrons have and so there are more electrons moving in the conduction band and therefore more heat.

  2. I am going to investigate what the resistivity is of a pencil lead. ...

    0.44 0.443 1.00 0.55 0.54 0.55 0.546 1.20 0.66 0.66 0.67 0.663 1.40 0.84 0.85 0.85 0.846 1.60 1.11 1.10 1.10 1.103 1.80 1.28 1.26 1.30 1.280 2.00 1.46 1.45 1.45 1.453 As you can see from the graph, the line of best fit does not pass through (0,0)

  1. Effect of changing the temperature on the resistance of a thermistor

    0.0025 0.9 75? 0.003 0.9 80? 0.0028 0.8 80? 0.00325 0.9 85? 0.003 0.8 85? 0.0033 0.8 90? 0.00315 0.75 90? 0.0035 0.8 95? 0.0033 0.75 95? 0.0037 0.8 100? 0.0034 0.75 100? 0.0039 0.75 There have list of equation: I will use this equation find out the resistance Resistance(R)

  2. The aim of my investigation is to determine the specific heat capacity of aluminium.

    Another source of inaccuracy was the assumption I made in performing the experiment that the reading of the thermometer was the temperature of the whole block. This was not the case as the temperature of the centre of the aluminium block, which was near the heating filament, would have been greater than that of the edge of the block.

  1. physics sensor coursework

    The sensitivity of a sensor is the ratio of change of output to input. As the graph does not show linearity, the sensitivity of the sensor is different at various light intensities. The change in sensitivity is very rapid though.

  2. Investigation into the resistance of a filament lamp.

    Circuit diagram: Apparatus: > Ammeter > Voltmeter > Variable Resistor > Filament lamp( 12V) > Connecting Wires > Crocodile clips( 2- to 3 to connect the > Thermometer > Power supply (D.C supply 12V) Preliminary Measurements: To get an idea of what range of measurements would get the best results,

  1. Characteristics of Ohmic and Non Ohmic Conductors.

    The LDR reacts differently. The light sensitive part of the LDR is a wavy track of cadmium sulphide. Light energy triggers the release of extra electrons to carry the current when the level of illumination changes accordingly. The line A marks the LDR in the shade while the line B marks the LDR in sunlight.

  2. Internal resistance investigation - I will conduct the following investigation with the aim to ...

    my results were all considerably lower than this because that calculation was for a perfect experiment which is almost impossible to achieve, as impurities in the electrolyte or the electrodes and the fast rate of cell deterioration mean that a lot less current is actually produced.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work