Truth that Contacting of Different Qualities Releases Energy (6)

As the second example of “contact between things of different qualities,” we now turn to a more technical case: the contact between electrical capacitors.　When two capacitors, originally isolated and storing different amounts of charge, are connected together, they release energy and lose part of their original energy.　Below, it is shown that such a combination without energy release is not possible.

Let's illustrate how differences in electrical properties release energy.
This section is technical, so you may skim this section and just focus on the conclusion.
Figure 2-4 shows the magnitude of energy E stored in a capacitor C holding charge Q.

Figure 2-5 shows two capacitors, each with the same capacitance C, independently holding different charges of 3Q and 1Q, respectively.
While Q represented thermal energy in thermodynamics, here it denotes the amount of electric charge. Since the charge amounts differ, the capacitors 1 and 2 have different voltages, indicating that their properties differ. When they are independent, the energies of capacitors 1 and 2 can be calculated separately.

The total energy when isolated (the sum of the energies held by the two capacitors) is calculated as

E1＋E2=10/2・Q２/C

Next time, I will show that when capacitors 1 and 2 are combined, they release and lose energy.

[ Author : Y. F. ]