An inductor, also called a coil or reactor, is a passive two-terminal electrical component that stores electrical energy in a magnetic field when electric current is flowing through it. An inductor typically consists of an electric conductor, such as a wire, that is wound into a coil. When the current flowing through an inductor changes, the time-varying magnetic field induces a voltage in the conductor, described by Faraday's law of induction. According to Lenz's law, the direction of induced electromotive force (e.m.f.) opposes the change in current that created it.
Designated a National Historic Landmark in 1963, the park is currently managed by the Central Park Conservancy under contract with the city government. The Conservancy is a nonprofit organization that contributes 85% of Central Park's $25 million dollar annual budget, and employs 80% of the park's maintenance staff.
National Capital Parks are the oldest parks in the National Park System. These parks began with the founding of the District of Columbia in 1790. The President appointed three Federal Commissioners to design a district ten miles (16 km) square on the Potomac River for the permanent seat of the Federal Government.n 1933 these National Memorials were added to the National Park System and the National Memorial function assigned to the National Park Service, except Perry's Victory Memorial, which was administered by a commission until it was added to the System in 1936.