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Lee's Disc Apparatus
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## Procedure for Performing  Simulation

1. Select the disc material from the drop down combo box.
3. Select the insulator from the drop down combo box.
4. Adjust the thickness of the insulator.
5. Place the insulator by clicking the 'Place Insulator' button.
6. After placing the insulator, start the steamer by clicking 'Start Steam' button.
7. After some time the heat chamber temperature(T1) and the Lee's disc temperature(T2) will become steady.
8. Then remove the object from the Lee's disc by clicking on the 'Remove Insulator' button (the 'Place Insulator' button will change to 'Remove Insulator' after step 5).
9. The temperature of T2 will rise again; stop the heater when the reading of T2 reaches 10 degrees above the steady temperature. The 'Stop Steam' button can be used to do this.
10. Now the temperature at the Lee's disc will start to drop. Start the stop watch, and note down the temperature at T2 from 5 degrees above the steady temperature  to 5 degrees below that at each 30 seconds. Using these points a graph has to be plotted and dT/dt can be obtained from it and the Κ value can be calculated.
11. The user can view the graph by clicking  on the 'show graph' check box.

## Procedure for Real lab

1. Determine the mean thickness of metal disc and bad conductor with a screw gauge.
2. Determine the diameter of  metal disc and bad conductor with  vernier calipers.
3. Find the mass M of the metal disc by a balance.
4. Keep the bad conductor between metal disc and steam chamber.
5. Introduce thermometers through holes in the steam chamber and in the metal disc.
6. Pass steam through the chamber until the temperature indicated by thermometers become steady and note the steady temperature.
8. Remove the steam chamber when the temperature of the metal disc is 10 0 C above it's steady temperature.
9. Start a stop clock and take time-temperature observation till the temperature of the disc is 10 0 C below it's steady state.
10. Plot a time-temperature graph.

## Find the Rate of Cooling:

 Time (s) Temperature (0C)

## Calculation

From the graph,

dT =...........0C

dt=............s

dT/dt=.........0Cs-1

Specific heat capacity of the metal disc c =...........JKg-1K-1

Coefficient of thermal conductivity of the given material ,

## Result

Coefficient of thermal conductivity of the given material,k =..........Wm-1K-1

Cite this Simulator:

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 Copyright @ 2020 Under the NME ICT initiative of MHRD