• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Effect of changing the temperature on the resistance of a thermistor

Extracts from this document...

Introduction

Name: Ray Li

Physics Coursework

Aim: Effect of changing the temperature on the resistance of a thermistor

I am going to find out has the temperature effects the thermistor’ resistance in the circuit.

Planning

Method:

  1. Clear the table and take off the needless thing
  2. Use the wires to link all the equipment to complete the circuits.
  3. Put about 25cm3 water in the beaker.  
  4. Turn on the gas to boiling the water.
  5. Look at the thermometer and  record the p.d and current each 5 C
  6. Repeat this experiment.
  7. Put all data into table.
  8. Calculation the resistance and draw the graphs.

The equation is: Resistance(R) = Potential different (p.d.)

                        Current (I)        

Appliance list:

Wires- Use these wires to link all appliances to complete the circuit.

Power Supply- Use these supply the energy into circuit.

Thermistor- I use this to change the resistance in the circuit.

Voltmeter- Measuring the volt in the circuit across the thermistor.

Ammeter- Measuring the current in the circuit through the thermistor.

Beaker- Have thermistor and water made above at same temperature.

Bunsen burner- I am boil the water and increasing the temperature of thermistor.

Thermometer- Measuring the temperature of the thermistor.

...read more.

Middle

45℃

0.0017

1.2

45℃

0.002

1.6

50℃

0.0018

50℃

0.0022

1.2

55℃

0.0021

1.2

55℃

0.0024

1.2

60℃

0.0022

1

60℃

0.00245

1.1

65℃

0.0023

1

65℃

0.0026

1

70℃

0.0025

0.95

70℃

0.0028

1

75℃

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) = Potential different (p.d.)

                    Current (I)

I use equation find out the average of resistance:

(Resistance1 + Resistance 2)÷2=Average of resistance.

...read more.

Conclusion

Slope A:

 (1000-570) / (55-35) = 21.5

The gradient is 21.5

Slope B:

(285.7-220.6) / (100 -80) = 4

The gradient is 4

In the second experiment graph:

Slope A:

(997 – 500) / (55 – 35) = 23.5

The gradient is 23.5

Slope B:

(242.4-192.3)/ (55-35) = 4.23

The gradient is 4.23

In the average of resistance

Slope A:

(970.55-535)/ (55-35) = 21.78

The gradient is 21.78

Slope B:

(280-206.45)/ (55-35) =3.68

The gradient is 3.68

The average gradient

Slope A gradient

21.78

Slope B gradient

3.68

In the graph if the gradient is large, there have large current flow in and the low volt, the resistance will high decrease. Also the gradient is small, the resistance will decrease is low.

All the graphs in 35℃ to 55℃ decrease very faster, but the end 80℃to 100℃ is decrease quite slow. This is same with my prediction graph.

Evaluation

In my experiment I should repeat few more times to have more data. This could make the result fair.

In my graphs have some points did not on the best-fit line. I could have some errors in my experiment. It could be read the voltmeter or ammeter not ready correct have some error. I should read quickly. And than the thermometer is not ready measuring the thermistor. Because the thermometer did not close the thermistor. So there have a little error to change the result. So I should use the stand to keep thermometer close the thermistor.

...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. Investigate how the temperature affects the resistance of a thermistor.

    All equipment must be kept the same in my experiment. The thermistor must be the same one throughout because different sizes of thermistors react differently to heat and they can be made in different ways to react more or less with heat than others.

  2. Investigate the relationship between temperature and resistance in a thermistor.

    0.23 11.46 11.42 11.52 49.83 49.65 50.09 49.86 100 0.25 0.24 0.25 11.42 11.42 11.50 45.68 47.58 46.00 46.42 Analysis From my graph I can clearly see that as the temperature increases the resistance decreases. This is because as the thermistor increases in temperature the lattice atoms move faster and

  1. The effect of temperature on the resistance of a thermistor

    I predict that the resistance will decrease with the increase of temperature. I think this not only because of scientific sources but my own. I predict that the graph will look something like this: Explanation of prediction: In my prediction I have stated that a change in temperature will affect the resistance of the thermistor.

  2. Investigating the effect of 'length' on the resistance of a wire

    31.88 80.0 2.59 0.06 43.17 90.0 2.60 0.06 43.33 The second set of results is shown in the table below: TABLE No2 Length of Wire (cm) Voltage (V) Current (A) Resistance (?) - rounded up to 2 d.p R=V/I 10.0 1.70 0.35 4.86 20.0 2.00 0.22 9.09 30.0 2.25 0.17

  1. Investigation into how the resistance of a thermistor varies with temperature.

    We will raise the temperature in exactly five degree intervals so we can see how the resistance varies steadily. Also, it would be harder to take or evaluate the results if there are random or larger intervals. Obtaining Evidence Results The key: * V1 = the voltage reading with one battery.

  2. Experiments with a thermistor

    The circuit is basically made up of a 5 V power supply with a thermistor and a resistance substitution box connected in series. A digital multi-meter is connected in parallel to the thermistor, to measure the potential difference across the thermistor.

  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. An Investigation into the Resistance of a Thermistor, its Application as a Sensor and ...

    This is the basic principle behind many electrical sensors. A potential divider is used to divide an input voltage into two, and the output voltage across one of the resistors is a fraction of the input voltage. The fraction is dependent on the ratio of R1 against R2. If one of the resistors is dependent on a physical stimulus,

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