Converting electrical energy into heat energy - Measuring with CASSY

In the experiment P2.3.4.3, the equivalence of electrical energy E_el and thermal energy E_th is established experimentally. The supplied electrical energy E_el is converted into heat E_th in the heating coil (or heating spiral). This leads to a temperature rise in the calorimeter (or water, in which the heating spiral is immersed). As the current I and the temperature ϑ are measured simultaneously as functions of the time t, the constant voltage U being known, the two energy forms can be registered quantitatively in units of wattsecond (Ws) and Joule (J) so that their numerical equivalence can be demonstrated experimentally:
E_el = E_th.