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Name: Joey L.
Status: student
Age: 16
Location: N/A
Country: N/A
Date: 2001-2002

I am currently enrolling in physics in my school, and my class have came across a question; it regards potential energy. I know that the symbol for potential energy is "U", but how did the symbol came about? I understand that "P" and "p" are both taken by "power" and "momentum", which I believe is the reason that "U" is chosen. However, which language or what abbreviation does the symbol "U" stands for??

More often than not the symbols used for various quantities in physics, chemistry, mathematics, and other fields of science, have no "intrinsic" meaning. For example, the letter "p" or "P" is also used for pressure, and for the element phosphorus. The letter "T" is often used for kinetic energy, and "V" for the potential energy instead of "U". In math, "x", "y", "z" commonly stand for variables; while the letters "i" through "q" are often used to denote numbers, especially integers.

In most texts, scientific papers and the like, the author will provide the definition of the symbols she/he is using or it is clear from the context of the subject. A silly example from chemistry: "He is a gas." means helium, of course, not the pronoun indicating a male has been vaporized.

Vince Calder

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