work is done to increase the temperature of the immersion heater and the water in the cavity surrounding the thermometer.uneven heating in the block means the temperature as measured by the thermometer may not be the same as in other parts of the block.thermal energy is transferred from the block to the environment.Alternatively, ensure the thermometer is read at eye level to remove any parallax error. We could also use an electronic temperature probe to avoid misreading the thermometer. These errors can be reduced by using the graphical method for the results discussed above as the line of best fit helps to remove anomalous results. ![]() limited precision on the Joulemeter, ammeter, voltmeter and timer.limited precision on the thermometer, usually only read to the nearest degree centigrade.Instrument errors (random) (these are relatively small in this experiment compared to other sources of error): The basic method gave the result c=960J/kg℃, the more advanced graphical method gave a result of c=870J/kg℃. We can immediately see the effect of some of the systematic errors on the results obtained using the basic and graphical data analysis methods. There are sources of error in this experiment from the instruments used to perform the experiment and from the method itself. So we can calculate the specific heat capacity from the graph using,įor our example data the gradient of the line is gradient = 38/33000, and the mass of the block is 1kg, so the specific heat capacity of the material is, Then we notice that the gradient of our line of best fit is just, ![]() If we write the specific heat capacity equation in the form, The line of best fit ensures that your conclusions are not biased by anomalous results at the beginning or end of the experiment by taking into account all other data points. If we did this analysis for the example data and a mass of 1kg, we would find, Δθ=42℃, ΔE=40,500J, so,Ī better way of using this data is to plot a graph of temperature against work done and draw a line of best fit. With this information and the mass of the metal block, m, you can calculate the specific heat capacity of the block using the key equation. 1 minute) and record in a table.įrom this table you can work out the change in energy, ΔE, and the change in temperature, Δθ.
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