The proof of mass vector.
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From: Sam Wormley on 25 Dec 2006 00:09 yen, ka-in wrote: > Randy Poe wrote: >> yen, ka-in wrote: >>> In three dimensional vector algebra, area HAS TO be a vector, >> Writing it in caps doesn't make it so. >> >> Why does area have to be a vector? >> >> What makes you think scalars can't exist in 3-space? > > Dear Randy, > > Thank you for your question. In 3D vector algebra, there are > four basic operations: addition, dot product, cross product, and > scalar multiplication. To get the area of the parallelogram generated > from vectors A and B, cross product has to be used: area=AXB; > so the area HAS TO be a vector. > Area is not a vector quantity. Inner Product(Dot Product) http://www.ies.co.jp/math/java/vector/naiseki_e/naiseki_e.html
From: Sam Wormley on 25 Dec 2006 00:14 yen, ka-in wrote: > Randy Poe wrote: >> yen, ka-in wrote: >>> In three dimensional vector algebra, area HAS TO be a vector, >> Writing it in caps doesn't make it so. >> >> Why does area have to be a vector? >> >> What makes you think scalars can't exist in 3-space? > > Dear Randy, > > Thank you for your question. In 3D vector algebra, there are > four basic operations: addition, dot product, cross product, and > scalar multiplication. To get the area of the parallelogram generated > from vectors A and B, cross product has to be used: area=AXB; > so the area HAS TO be a vector. > Area is not a vector quantity. Inner Product(Dot Product) http://www.ies.co.jp/math/java/vector/naiseki_e/naiseki_e.html
From: Eric Gisse on 25 Dec 2006 03:41 yen, ka-in wrote: > Randy Poe wrote: > > yen, ka-in wrote: > > > In three dimensional vector algebra, area HAS TO be a vector, > > > > Writing it in caps doesn't make it so. > > > > Why does area have to be a vector? > > > > What makes you think scalars can't exist in 3-space? > > Dear Randy, > > Thank you for your question. In 3D vector algebra, there are > four basic operations: addition, dot product, cross product, and > scalar multiplication. To get the area of the parallelogram generated > from vectors A and B, cross product has to be used: area=AXB; > so the area HAS TO be a vector. No, retardo. Area of the parallelpiped is the *absolute value* of A x B.
From: Phineas T Puddleduck on 25 Dec 2006 09:45 On 2006-12-25 04:33:44 +0000, "yen, ka-in" <yenkain(a)yahoo.com.tw> said: > Thank you for your question. In 3D vector algebra, there are > four basic operations: addition, dot product, cross product, and > scalar multiplication. To get the area of the parallelogram generated > from vectors A and B, cross product has to be used: area=AXB; > so the area HAS TO be a vector. And the area is only defined for flat space. -- For me, it is far better to grasp the Universe as it really is than to persist in delusion, however satisfying and reassuring. Carl Sagan -- Posted via a free Usenet account from http://www.teranews.com
From: Pmb on 25 Dec 2006 10:01
"Phineas T Puddleduck" <phineaspuddleduck(a)googlemail.com> wrote in message news:458fd74a$0$15523$88260bb3(a)free.teranews.com... > On 2006-12-25 04:33:44 +0000, "yen, ka-in" <yenkain(a)yahoo.com.tw> said: > >> Thank you for your question. In 3D vector algebra, there are >> four basic operations: addition, dot product, cross product, and >> scalar multiplication. To get the area of the parallelogram generated >> from vectors A and B, cross product has to be used: area=AXB; >> so the area HAS TO be a vector. > > And the area is only defined for flat space. I don't follow. Who was it that claimed that area was a vector???? That's total nonsense. Taking the cross product of two vectors does yield another vector. The *magnitude* of the vector being equal to the parallelagram defined by the two vectors. Regards Pete |