definition of Wikipedia
Advertizing ▼
In mathematics, physics, and logic, Pappus' centroid theorem (also known as the Guldinus theorem, Pappus–Guldinus theorem or Pappus' theorem) is either of two related theorems dealing with the surface areas and volumes of surfaces and solids of revolution.
The theorem is attributed to Pappus of Alexandria and Paul Guldin.
The first theorem states that the surface area A of a surface of revolution generated by rotating a plane curve C about an axis external to C and on the same plane is equal to the product of the arc length s of C and the distance d traveled by its geometric centroid.
For example, the surface area of the torus with minor radius r and major radius R is
The second theorem states that the volume V of a solid of revolution generated by rotating a plane figure F about an external axis is equal to the product of the area A of F and the distance d traveled by its geometric centroid.
For example, the volume of the torus with minor radius r and major radius R is
This geometry-related article is a stub. You can help Wikipedia by expanding it. |
sensagent's content
Dictionary and translator for handheld
New : sensagent is now available on your handheld
Advertising ▼
Webmaster Solution
Alexandria
A windows (pop-into) of information (full-content of Sensagent) triggered by double-clicking any word on your webpage. Give contextual explanation and translation from your sites !
SensagentBox
With a SensagentBox, visitors to your site can access reliable information on over 5 million pages provided by Sensagent.com. Choose the design that fits your site.
Business solution
Improve your site content
Add new content to your site from Sensagent by XML.
Crawl products or adds
Get XML access to reach the best products.
Index images and define metadata
Get XML access to fix the meaning of your metadata.
Please, email us to describe your idea.
Lettris
Lettris is a curious tetris-clone game where all the bricks have the same square shape but different content. Each square carries a letter. To make squares disappear and save space for other squares you have to assemble English words (left, right, up, down) from the falling squares.
boggle
Boggle gives you 3 minutes to find as many words (3 letters or more) as you can in a grid of 16 letters. You can also try the grid of 16 letters. Letters must be adjacent and longer words score better. See if you can get into the grid Hall of Fame !
English dictionary
Main references
Most English definitions are provided by WordNet .
English thesaurus is mainly derived from The Integral Dictionary (TID).
English Encyclopedia is licensed by Wikipedia (GNU).
Copyrights
The wordgames anagrams, crossword, Lettris and Boggle are provided by Memodata.
The web service Alexandria is granted from Memodata for the Ebay search.
The SensagentBox are offered by sensAgent.
Translation
Change the target language to find translations.
Tips: browse the semantic fields (see From ideas to words) in two languages to learn more.
last searches on the dictionary :
computed in 0.031s