Electric power is transformed to other forms of energy when electric charges move through an electric potential difference, which occurs in electrical components in electric circuits. From the standpoint of electric power, components in an electric circuit can be divided into two categories: Passive devices or loads: When electric charges move through a potential difference from a higher to a lower voltage, that is when conventional current (positive charge) moves from the positive (+) terminal to the negative (â) terminal, work is done by the charges on the device.
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