What is Circumference?Date: 06/25/2001 at 12:48:12 From: raman Subject: What is circumference? What is circumference? My friend told me it's somewhat like the measurement of the outside of a circle, but I don't understand that. Can you help? Date: 06/25/2001 at 13:31:58 From: Doctor Ian Subject: Re: What is circumference? Hi Raman, Imagine a square, like A B +-----+ | | | | +-----+ D C The 'perimeter' of the square is the sum of the distances perimeter = AB + BC + CD + DA That is, it is the length of the _path_ that you would have to take to move all the way around the square, returning to the place where you started. We can extend the definition to regular polygons with more sides, e.g., A _____ B / \ F / \ C perimeter = AB + BC + CD + DE + EF + FA \ / \_____/ E D (A 'regular' polygon is a polygon whose sides and angles are identical. So a square is a regular polygon, but a parallelogram is not.) A circle is basically a regular polygon with an infinite number of sides. For a circle, 'circumference' and 'perimeter' mean the same thing. The American Heritage Dictionary gives these definitions for circumference: http://www.bartleby.com/61/55/C0365500.html 1. The boundary line of a circle. 2a. The boundary line of a figure, area, or object. 2b. abbreviation c or circ. The length of such a boundary. The word is originally from Latin circumferentia, from circumferns, circumferent-, present participle of circumferre, meaning "to carry around." Does this help? Write back if you'd like to talk about this some more, or if you have any other questions. - Doctor Ian, The Math Forum http://mathforum.org/dr.math/ |
Search the Dr. Math Library: |
[Privacy Policy] [Terms of Use]
Ask Dr. Math^{TM}
© 1994- The Math Forum at NCTM. All rights reserved.
http://mathforum.org/dr.math/