Half-life (symbol t1⁄2) is the time required for a quantity to reduce to half of its initial value. The term is commonly used in nuclear physics to describe how quickly unstable atoms undergo radioactive decay or how long stable atoms survive. … The converse of half-life is doubling time.
De plus, What is the story behind half-life?
The original Half-Life, Valve’s first product, was released in 1998 for Windows to critical and commercial success. Players control Gordon Freeman, a scientist who must survive an alien invasion. … Set before Half-Life 2, players control Freeman’s ally Alyx Vance in her quest to defeat the alien Combine.
Ainsi What does living a half-life mean? 1 : the time required for half of something to undergo a process: such as. a : the time required for half of the atoms of a radioactive substance to become disintegrated.
What is the best definition of half-life?
half-life. n. The time required for half the nuclei of a specific radionuclide or radioactive substance to undergo radioactive decay. physical half-life. The time required for half the quantity of a drug or other substance deposited in a living organism to be metabolized or eliminated by normal biological processes.
What is the half-life symbol called?
The Lambda logo (λ) is a symbol found frequently in the Half-Life universe. It represents the Greek letter « Λ » (lowercase « λ »), and is a radioactive decay constant used in the half-life equation.
Why is Half-Life important?
Knowing about half-lives is important because it enables you to determine when a sample of radioactive material is safe to handle. … They need to be active long enough to treat the condition, but they should also have a short enough half-life so that they don’t injure healthy cells and organs.
Is Half Life uplink cannon?
The subject matter of this article does not take place in the « real » Half-Life and Portal universe and is considered non-canon. This article is about the demo. For the short film, see Half-Life: Uplink (film). Half-Life: Uplink is the demo version of Half-Life.
Who are the bad guys in Half-Life?
The Combine, abbreviated as CMB, officially named the Universal Union and referred to by the Citadel as Our Benefactors, is the main antagonistic force of the Half Life series, first making their debut in Half-Life 2.
Do humans have a half-life?
The biological half-life of water in a human is about 7 to 14 days. It can be altered by behavior. … This has been used to decontaminate humans who are internally contaminated with tritiated water (tritium).
How long is a half-life?
Half-life is defined as the time required for half of the unstable nuclei to undergo their decay process. Each substance has a different half-life. For example, carbon-10 has a half-life of only 19 seconds, making it impossible for this isotope to be encountered in nature.
What is half-life in psychology?
Half-life of knowledge refers to the number of years that it would take for half of the information or knowledge available in a field of study to become defunct or superseded by new information.
What are the two definitions of half-life?
Half-life is the time it takes for half of the unstable nuclei in a sample to decay or for the activity of the sample to halve or for the count rate to halve. Count-rate is the number of decays recorded each second by a detector, such as the Geiger-Muller tube. … The half-life of radioactive carbon-14 is 5,730 years.
What is the definition of a half-life quizlet?
Half life definition. the average time it takes for the number of nuclei in a radioactive isotope sample to halve. the radioactivity of a sample always. decreases over time.
What is a half-life in earth science?
Half-life is a term that describes time. The definition is: The time required for one-half of the radioactive (parent) isotopes in a sample to decay to radiogenic (daughter) isotopes. In other words, it is the lifetime of half the radioactive isotopes in a system.
What is this symbol ρ?
Rho (uppercase/lowercase Ρ ρ) is the 17th letter of the Greek alphabet. It is used to represent the « r » sound in Ancient and Modern Greek. In the system of Greek numerals, it has a value of 100.
What is the meaning of λ?
Lambda (/ˈlæmbdə/; uppercase Λ, lowercase λ; Greek: λάμ(β)δα, lám(b)da) is the 11th letter of the Greek alphabet, representing the sound /l/. In the system of Greek numerals, lambda has a value of 30. Lambda is derived from the Phoenician Lamed. . Lambda gave rise to the Latin L and the Cyrillic El (Л).
Why is the half life symbol lambda?
The Lambda symbol is used in the half-life equation to represent the decay constant (i.e. the rate of radioactive decay in an element). The Lambda logo is also used to denote the wavelength of a sound or light emission.
Why is half-life important in nuclear medicine?
In a nutshell, the radiological half-life is important in radiation control because long-lived radionuclides, once released, are around for longer time periods than are shorter-lived species. Long-lived radionuclides released to the environment will be present for longer times than short-lived nuclides.
What is the importance of half-life for radioactive waste management?
Accurate nuclear decay data, such as half-lives, are important input parameters in the development of technical solutions for safe long-term disposal of nuclear waste. I is a fission product of 235U considered as one of the most important dose contributors in the nuclear waste disposal storages in the future.
How do scientists use half-life?
Scientists can use the half-life of Carbon-14 to determine the approximate age of organic objects less than 40,000 years old. By determining how much of the carbon-14 has transmutated, scientist can calculate and estimate the age of a substance. This technique is known as Carbon dating.
Is Half-Life a place in the West canon?
Canon – that collection of ideas, characters, and events held to be ‘official’ and existing within the creators’ universe. Which is to say everything that Half-Life: A Place in the West is not. The comic, as pure fan fiction, is stringently non-canonical. … Instead, it found its way into the comic.
Are Half-Life expansions canon?
According to the wiki Valve refuses to consider anything as strictly canon. However, the community has settled on the thought that sanctioned games and books that do no directly contradict the existing story are considered canon.
Is Half-Life and Portal connected?
Portal is a puzzle game set in the Half-Life universe, developed by Valve Corporation. It was initially released alongside Episode Two in The Orange Box on October 10, 2007. … The storyline continues from the end of Portal. The player again controls Chell in the single-player campaign.
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