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.
For works created by individual authors on or after January 1, 1978, copyright protection begins at the moment of creation and lasts for a period of 70 years after the author's death. In the case of a joint work (prepared by two or more authors) the term lasts for 70 years after the last surviving author's death. For works made for hire, and for anonymous and pseudonymous works, copyright protection generally lasts for 95 years from publication or 120 years from creation, whichever is shorter.
The duration of copyright protection is governed by the Sonny Bono Copyright Term Extension Act of 1998. The easiest rule to state is that Copyrights have expired on all United States works registered or published prior to 1923.he law provides that in no case will the term of copyright for works in this category expire before December 31, 2002, and for works published on or before December 31, 2002, the term of copyright will not expire before December 31, 2047.