抄録
At upper secondary schools, students learn the formula that represents the electrostatic energy stored in a capacitor. However, it is not generally easy to do experiments to validate the formula in classroom hours. We have developed a power meter that can measure the output power of a hand generator. This power meter can calculate the total energy that passed through it. Using this function, we can measure the energy stored in a capacitor without any additional apparatus. It is very significant for the education related to “energy” that the amount of the energy can be directly measured. Leaning from experiments is effective to understand the electrostatic energy stored in capacitor, which has been verified by lesson practices in a college of technology. From the experiments, students can also learn that the energy loss is inevitable in energy conversion process, that errors actually occur in the measurements, and that the actual capacitor has a series resistance and is different from the ideal circuit model of a capacitor.
