neutral flame (oxygas welding). A flame that uses the chemically correct ratio of fuel gas and oxygen. A
neutral flame in an oxyacetylene torch has an almost white, rounded inner cone and an envelope of light blue flame. Too much oxygen changes a neutral flame into an oxidizing flame, and the inner cone becomes pointed. Too much acetylene changes a neutral flame into a carburizing, or reducing, flame, and a feather appears around the inner cone.
neutralization (electronic circuit). The use of external circuit devices to cancel, or neutralize, the effect of interelectrode capacitance in an electron tube.
neutral plane (electrical machine). An imaginary line perpendicular to the lines of magnetic flux passing between the field poles of an electric motor or generator. If the brushes are mounted along this neutral plane, the segments of the commutator they short across have the same electrical potential, and there will be no sparking at the brushes.
neutral position of the rotating magnet (aircraft magneto). The position of the rotating magnet in an aircraft magneto in which the poles of the magnet are directly between the pole shoes in the magneto housing. When the magnet is in its neutral position, no magnetic flux flows through the core of the magneto coil.

neutral static stability (aircraft stability). A condition of static stability in which an aircraft, if disturbed from its condition of rest, will neither attempt to deviate farther from this condition nor to return to its original condition.
neutron. A particle in the nucleus of an atom which has mass, but no electrical charge. A neutron has about the same mass as a proton, and it adds weight to the atom, but does not affect its chemical behavior. Neutrons serve as a “cement” to hold the protons in the nucleus of an atom.
newton. a unit of force in the metric system. One newton is the amount of force needed to cause a mass of one kilogram (1,000 grams) to accelerate at a rate of one meter per second each second the force acts on it.
One newton is equal to 100,000 dynes, or 2.248 . 10-1 pound.
Newton’s first law of motion. The law of physics which describes inertia. An object at rest will try to remain at rest, and a moving object will try to keep moving in the same direction, at the same speed, unless it is acted upon by an outside force.
Newton’s metal. A low-melting-point metal used for the fusible links in an automatic sprinkler systems. Newton’s metal, which is made of 50% bismuth, 31% lead, and 19% tin, melts at 95° Celsius.
Newton’s second law of motion. The law of physics concerning acceleration. The amount of acceleration imparted to an object by a force is directly proportional to the amount of force acting on it, and inversely proportional to the mass of the object. The greater the force, the greater the acceleration, and the greater the mass, the less the acceleration.
Newton’s third law of motion. The law of physics relating to action and reaction. For every action, there is an equal and opposite (equal amount and opposite direction) reaction.