Tau
From Wikipedia, the free encyclopedia.

Tau (Τ τ) is the 19th letter of the Greek alphabet and has a numeric value of 300.

The lower-case letter τ is used as a symbol for:

• Torque, the rotational force in mechanics.
• The elementary tauon particle in particle physics.

The original article can be found at: http://en.wikipedia.org/wiki/Tau.
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