Simulator link: https://vlab.amrita.edu/repo/PHY/TDM/LeesDiscApparatus/Leesdiscapparatus.swf
Procedure for Performing Simulation
- Select the disc material from the drop down combo box.
- Adjust disc's mass, height and radius by using the sliders.
- Select the insulator from the drop down combo box.
- Adjust the thickness of the insulator.
- Place the insulator by clicking the 'Place Insulator' button.
- After placing the insulator, start the steamer by clicking 'Start Steam' button.
- After some time the heat chamber temperature(T1) and the Lee's disc temperature(T2) will become steady.
- 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).
- 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.
- 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.
- The user can view the graph by clicking on the 'show graph' check box.
Procedure for Real lab
- Determine the mean thickness of metal disc and bad conductor with a screw gauge.
- Determine the diameter of metal disc and bad conductor with vernier calipers.
- Find the mass M of the metal disc by a balance.
- Keep the bad conductor between metal disc and steam chamber.
- Introduce thermometers through holes in the steam chamber and in the metal disc.
- Pass steam through the chamber until the temperature indicated by thermometers become steady and note the steady temperature.
- Remove the bad conductor.
- Remove the steam chamber when the temperature of the metal disc is 10 0 C above it's steady temperature.
- Start a stop clock and take time-temperature observation till the temperature of the disc is 10 0 C below it's steady state.
- Plot a time-temperature graph.
Find the Rate of Cooling:
From the graph,
Specific heat capacity of the metal disc c =...........JKg-1K-1
Coefficient of thermal conductivity of the given material ,
Coefficient of thermal conductivity of the given material,k =..........Wm-1K-1