# Nu

**nu**- A letter of the Greek alphabet.
**Nuclear and Particle Physics**- Lists all Particle Physics topics in the Encyclopaedia
**Nuclear and Particle Physics Books**- Lists all Particle Physics Books in the Encyclopaedia
**Nuclear and Particle Physics Calculations**- Lists all Particle Physics Calculations in the Encyclopaedia
**Nuclear and Particle Physics Conversions**- Lists all Particle Physics Conversions in the Encyclopaedia
**Nuclear and Particle Physics Weblinks**- Lists all Particle Physics Weblinks in the Encyclopaedia
**Nuclear Binding Energy**- Energy needed to break an atomic nucleus into separate protons and neutrons.
**Nuclear Cross Section**- The effective area that a given nucleus presents as a target to a bombarding particle, giving a measure of the probability that the particle will induce a reaction.
**Nuclear Energy**- Energy stored in the nucleas of an atom.
**Nuclear Equations**- Show the changes that take place in the nuclei.
**Nuclear Fusion**- The combining of light nuclei to form a heavier nucleus.
**Nuclear Reaction**- A reaction involving the nucleus of an atom that alters the energy, composition or structure of the atom.
**Nuclear Reactor**- An apparatus in which nuclear fission may be sustained in a self supporting chain reaction.
**Nucleate**- To form a central part around which other parts can attach.
**Nucleation**- The initial stage in a phase transformation.
**Nuclei**- The plural of nucleus, the central part of an atom that contains the protons and neutrons.
**Nucleic Acid**- A polymer made of repeating nucleotides. Examples are DNA and RNA.
**Nucleoid**- In prokaryotes a region of the cell which contains chromosomal DNA.
**Nucleon**- Either a proton or a neutron.
**Nucleoside**- A nucleotide base bound to a five-carbon sugar.
**Nucleotide**- A molecule which is a basic building block of nucleic acids and which plays a key role in energy transfer in biochemical reactions.
**Nucleotide Base**- A heterocyclic nitrogen-containing base that is a constituent of nucleotides.
**Nucleus**- The central part of an atom that contains the protons and neutrons.
**Nucleus**- The nucleus of eukaryotes is a membrane bound organelle, which contains the chromosomal DNA.
**Nuclide**- An atom or ion with a specified mass number and atomic number.
**Nuclide Symbol**- A symbol for an nuclide that contains the mass number as a leading superscript and the atomic number as a leading subscript.
**Null**- A low or minimum point on a graph. A minimum pressure region in a room.
**Null Experiment**- An experiment which, after being executed, yields no result.
**Null Hypothesis**- Proposes a general or default position, such as that there is no relationship between two measured phenomena, or that a potential treatment has no effect.
**Null Set**- The null set is a set that contains no objects. Also known as the empty set.
**Null Space of a Matrix**- The null space of a m by n matrix A is the set of all vectors x in R
^{n}such that Ax = 0. **Nullity of a Linear Transformation**- This is the dimension of its null space.
**Nullity of a Matrix**- This is the dimension of its null space.
**Number**- A mathematical entity that may indicate quantity or amount of units.
**Number Drills**- This system of numbering drills is no longer used, but may be of use in deciphering old drawings.
**Number Line**- A line on which each point represents a real number.
**Number of Gram Equivalent Weights**- The number calculated by dividing the mass of a substance (in grams) by the equivalent weight of the substance.
**Number Representation**- The representation of numbers by agreed sets of symbols according to agreed rules.
**Number System**- Any system for the representation of numbers.
**Numeral**- A numeral is just an object or symbol that stands for a number. For example, 5 is the Arabic numeral for five, and V the Roman numeral for five.
**Numerator**- The quantity or value on the top of a fraction.
**Numeric**- Composed wholly or partly of digits.
**Numeric Coding**- A system of coding in which information is represented by digits.
**Numerical Analysis**- The study of methods for approximation of solutions of various classes of mathematical problems including error analysis.
**Numerical Analysis Books**- Lists all Numerical Analysis Books in the Encyclopaedia
**Numerical Analysis Calculations**- Lists all Numerical Analysis Calculations in the Encyclopaedia
**Numerical Analysis Conversions**- Lists all Numerical Analysis Conversions in the Encyclopaedia
**Numerical Analysis Source Code**- Lists all Numerical Analysis Source Code in the Encyclopaedia
**Numerical Analysis Weblinks**- Lists all Numerical Analysis Weblinks in the Encyclopaedia
**Numerical Control**- Any controlled equipment that allows an operator to program its movement by entering a series of coded numbers and symbols.
**Nusselt Number**- A number expressing the ratio of convective to conductive heat transfer between a solid boundary and a moving fluid.
**Nut**- A type of hardware fastener with a threaded hole.
**Nutating**- Moving an antenna feed point in a conical pattern so that the polarization of the beam does not change.
**Nutation**- The oscillation of the axis of any rotating body, as a gyroscope rotor.