Physics.ie - Focus on Physics

Glossary N

Nanotechnology
This is engineering at the atomic scale
and it is bringing cutting edge science into industry by creating new
applications for the electronics, pharmaceutical, IT and
biotechnology industries. The first mention of this technology
was in a talk given by Richard Feynman in 1959.
Visit our Nanotechnology website The Nano Show.
Neutrino
A lepton with no electric charge. Neutrinos
participate only in weak and gravitational interactions and are
therefore very difficult to detect. There are three known types
of neutrinos, all of which have very little mass.
Neutron
An uncharged elementary particle found
in the nucleus of every atom except hydrogen. A baryon with electric
charge zero; it is a fermion with a basic structure of two down
quarks and one up quark (held together by gluons). The neutral
component of an atomic nucleus is made from neutrons. Different
isotopes of the same element are distinguished by having different
numbers of neutrons in their nucleus.
Nucleus
The center, usually of the central piece
of an atom. The nucleus of an atom is composed of protons and
neutrons, which are, in turn, composed of quarks. The nucleus
of an atom is about 1000 to 10,000 times smaller than the size
of an atom. The size of the atom is defined by the orbit of the
electrons.
Newton’s Rings
A curved piece of glass on a flat piece
of glass is illuminated from above. A pattern of rings (light
and dark) appears in the curved piece of glass. This is a result
of interference from reflection.
Neutron Star
Neutron stars are one of the possible
ends for a star. They result from massive stars which have mass
greater than 4 to 8 times that of our sun. After these stars have
finished burning their nuclear fuel, they undergo a supernova
explosion. This explosion blows off the outer layers of a star
into a beautiful supernova remnant. The central region of the
star collapses under gravity. It collapses so much that protons
and electrons combine to form neutrons. Hence the name “neutron
star”.
Skip to toolbar