Atoms have electron shells with a certain number of electrons, and the outermost shell is the valence shell, which determines chemical reactions. Elements in the same group have the same number of electrons available for reactions. Charge number determines an atom’s charge during ionic reactions. Transitional elements can bond with different elements, and group IV […]
A heat number is a code printed on metal to track its origins and is important for quality control. It includes information on the furnace used, casting year, and casting number. The number can be used to trace materials, match replacement parts, and investigate accidents. Manufacturers can use it even if not required by law. […]
A matching number vehicle is one that is built entirely from the same parts it came off the assembly line with, and is worth more to serious collectors. Authenticating a pure correct and stock vehicle involves comparing parts to the original build sheet. Some vehicles are difficult to identify as original due to racing and […]
The Kappa number measures the amount of lignin in pulp and determines how much bleach is needed for white paper. A standardized test with potassium permanganate solution is used to determine the number, which is important for plant efficiency and batch papermaking. Techniques like washing pulp can lower the number, and records are kept to […]
The Reynolds number is a dimensionless number used in fluid mechanics to determine the turbulence or absence of turbulence of a fluid. It is defined as the ratio of inertial forces to viscous forces and is named after Osborne Reynolds. The number is used in various applications, including friction factor calculations and modeling the flow […]
The Harmonized Tariff Number is an identification code used for international trade. It allows for efficient identification of goods for legal and financial regulations. The number can be traced via the Harmonized System, which provides naming and numbering conventions for items shipped worldwide. There are 21 sections in the Harmonized System, with subsections identifying products […]
A tariff number is a six-digit code assigned to imports or exports based on the item’s category. The Harmonized Tariff Schedule of the United States (HTS) assigns these codes and is regulated by the United States International Trade Commission (ITC). The HTS is divided into 99 chapters, and each asset is assigned a rate number […]
Flight numbers are codes that identify airplanes and their flight paths. Airlines can create their own flight numbers, usually consisting of an airline code and a number sequence. There are some patterns adopted by airlines, but they have the autonomy to assign their own flight numbers. Flight numbers help passengers locate and identify flights, and […]
Imaginary numbers have a square that is a negative real number and are represented by the letter i. They were once thought to be fictitious but are now accepted and used in fields such as quantum mechanics and electrical engineering. They can be represented on a graph with the imaginary number axis perpendicular to the […]
Natural numbers are represented by 1, 2, 3, and so on, and include 0 if defined as non-negative integers. They are whole numbers used for counting or ordering, and are only positive. Zero was created by the Maya and Olmec civilizations, but the Indian usage was adopted by civilizations like the Greeks. Natural numbers are […]
The magnetic quantum number (mo ml) explains how electrons move within an atom’s subparticles. It falls between -1 and 1 and identifies the direction of movement. Other quantum numbers determine energy state, spin, and momentum. These calculations predict how energy responds to external forces and changes in motion. The magnetic quantum number is represented by […]
The term “golden number” can refer to the golden ratio in mathematics or to a number used in the Metonic cycle, an astrological sequence discovered by Meton of Athens. The Metonic cycle is used to calculate the date of Easter and is still used in some situations today. The golden number helps determine which lunar […]
The mass number of an atom is the sum of protons and neutrons in the nucleus. It determines the element and isotope. Different isotopes result from radioactive decay. The atomic mass is a measure of an atom’s mass and is expressed in atomic mass units. The mass number of an atom specifies the number of […]
Avogadro’s number is the amount of atoms in 12 grams of 12C. Amedeo Avogadro was the first to state that the volume of a gas is proportional to how many atoms it has. His law states that equal volumes of gases contain the same number of particles. The constant can be expressed as (p1)(V1)/(T1)(n1) = […]
Ordinal numbers indicate the position of something in a sequence. They are similar to cardinal numbers, but with added letters. Georg Cantor invented them in 1897 as part of set theory. Ordinal numbers are commonly used to count places and grade levels. An ordinal number is a number that indicates where in sequence something is […]
A number cruncher works with numbers and can be a computer, software application, or a person such as a financial analyst. The technology is used to manipulate data and create new data sets. A number cruncher is one of those exciting-sounding terms that means pretty much what it sounds like: it’s a thing or person […]
The atomic number is the number of protons in an element’s nucleus, determining its unique properties. Mass number is the sum of protons and neutrons, and isotopes have varying numbers of neutrons. The periodic table groups elements by atomic number, with columns based on electron arrangement. The atomic number is the number of protons – […]
A new prime number, M77232917, with over 77 million digits, was discovered by electrical engineer John Pace through the Great Internet Mersenne Prime Search (GIMPS) project. Prime numbers have been used historically for encoding messages and are now used in computer encryption. Mersenne primes are found by continuously multiplying two together and subtracting one. A […]
Prime numbers are integers greater than one with exactly two divisors. The ancient Greeks studied prime numbers, but interest waned until the mid-17th century. Mathematicians continue to find new primes using methods like Euclid’s formula and the sieve of Eratosthenes. Computers are now used to find large primes, but human effort is still required to […]
A part number is a numerical identification assigned to an item for ease of identification and inventory. It helps sellers match the correct item with the reference item from a parts catalog. Part numbers are used in salvage yards, classic and collector’s vehicles, and for registration purposes. They aid in the recovery of stolen goods […]
