Simulator link: https://vlab.amrita.edu/repo/PHY/TDM/Thermistor/Thermistor.swf
Procedure
For Real Lab
- Connections are made as shown in the figure.
- Place the thermistor in an oil bath using the heating arrangement.
- Note the room temperature (T0).
- Turn on the power supply and fix to a constant voltage.
- Note the current readings using a digital multimeter or a milliammeter.
- Corresponding resistance is found , using equation and is noted as R0.
- Vary the temperature of the oil bath using the heating arrangement.
- Note the current readings at regular intervals of temperatures.
- Corresponding resistances R is found using the same equation.
- From the readings, logR-logR0, 1/T-1/T0 is calculated.
- Value of β is calculated from equation
- Temperature coefficient of resistance is found from the equation, .
- Repeat the experiment for another voltage.
For Simulation
- Click on ‘show circuit diagram’ for displaying the circuit.
- Place the mouse pointer over the components and click to drag wire.
- After getting connected,click on ‘Power On ‘button in the variables region to start and maintain a constant voltage.
- Select the desired room temperature and choose any thermistor from drop down menu.
- Corresponding current reading is shown in milliammeter.
- Resistance for that value of voltage is found out using equation,
- Increase the temperature using the slider shown in variables region.
- Repeat the experiment for different values of voltages and different thermistors.
Observations
Result
The material constant of thermistor,ß=
The temperature coefficient of thermistor,α=..........(K-1)