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Revision as of 14:54, 8 December 2002 by Tarquin (talk | contribs)(diff) ← Previous revision | Latest revision (diff) | Newer revision → (diff)In mathematics, eccentricity is a parameter associated with every conic section. It can be thought of as a measure of how much the conic section deviates from being circular. In particular:
- The eccentricity of a circle is zero.
- The eccentricity of an ellipse is greater than zero and smaller than 1
- The eccentricity of a parabola is 1.
- The eccentricity of a hyperbola is greater than 1.
To calculate the eccentricity of any ellipse, measure the semi-major axis and call it a. Measure the semi-minor axis and call that measurement b. Now:
- eccentricity = e = √( 1 - b/a)
where √ is the square root sign. In astronomy, the eccentricity of an orbit can be calculated using this formula.
In popular usage, eccentricity refers to unusual or odd behavior on the part of a person.