Natural Chemical Species

(n.) A chemical species that exists in nature.

Natural Satellite

(n.) A celestial body that orbits a planet, such as the Moon around the Earth.

Neutral

(adjective) Refers to an aqueous solution with a pH equal to 7. This solution contains equal, small quantities of hydrogen ions H⁺ and hydroxide ions HO^-.

Newton, Isaac (1642-1727)

Renowned English mathematician, physicist, astronomer, and philosopher. Born in Woolsthorpe (Lincolnshire), he became immortalized through his discovery of the laws of universal gravitation and the decomposition of light. Concurrently with Leibniz, he discovered the foundations of differential calculus.

Newton

(n.m.) The legal unit of measurement for weight, symbolized as N.

Night

(n.f.) The interval of time between sunset and sunrise.

Nitrogen

(n.) Atom with atomic number Z equal to 7. It therefore has 7 electrons revolving around a nucleus containing 7 protons and often 7 neutrons. Its symbol is N. Its model is a blue sphere.

Node

(n.m.) A point of contact for at least three electrical wires in a circuit with branches.

Nominal Intensity

(noun) The current intensity that must flow through an electrical device for it to function normally.

Nominal Power

(n.f.) Power received by a device under its normal conditions of use. It is indicated on the device.

Nominal Voltage

(n.) Electrical voltage that should exist at the terminals of a receiver for it to function normally.

Non-Renewable Energy Source

(n.) An energy source that is depleted because it renews very slowly over millions of years, such as oil, coal, and natural gas.

Nuclear Power Plant

(n.) Plant that converts energy released by the fission of heavy nuclei into electrical energy.

Nylon

(n.m.) A plastic material. A synthetic textile fiber.