(P) Specific Heat Capacity

• To investigate a solid material (e.g copper), you'll need a block of the material with 2 holes in it ( for the heater and for the thermometer)
• 1. Measure the mass of the block, then wrap it up in an insulating layer (e.g newspaper) to reduce the energy transferred from the block to the surroundings
• 2. Measure the initial temperature of the block and set the potential difference, V, of the power supply to 10V.
• 3. Turn on the power supply and start a stop watch
• 4. When you turn on the power, the current in the circuit (e.g the moving charges) does work on the heater, transferring energy electrically from the power supply to the heater's thermal energy store. This energy is then transferred to the material's thermal energy store by heating (increase in temperature)
• 5. As the block heats up, take readings of the temperature and current, I, every minute for 10 minutes. You should find that the current through the circuit doesn't change as the block heats up
• 6. When you've collected enough readings, turn off the power supply. Using your measurement of the current, and the potential difference of the power supply, you can calculate the power supplied by the heater using P =VI.
• You can use the formula E = Pt to calculate how much energy has been transferred to the heater at the time of each temperature reading (t is time in (s) since the experiment began)
• 7. If you assume all the energy supplied to the heater has been transferred to the block, you can plot a graph of energy transferred to the thermal energy store of the block against temperature
• 8. Find the gradient of the straight part of the graph (∆θ/∆E). The specific heat capacity of the block will be (1/(gradient x mass of the block))
• 9. You can repeat the experiment with different materials to see how their specific heat capacities compare