Re: magnetic field

From: E. Rosten (look_at_my.sig)
Date: 09/27/04 

Date: Mon, 27 Sep 2004 10:31:53 +0100

Repeating Rifle wrote:

> What is a tensor you my ask. Rather than giving a circular argument I
will
> present *stress* as an example. Inside a stressed medium there will be a
> combination of tensile and shear stresses. This combination is an
entity by
> itself, in which tensile and shear stresses cannot be separated out.

Shear stress can always be seperated out: you can represent any
combination of shear and tensile stress as pure tensile stress (google
for Mohr's Circle).

The Mohr's Circle operation is just a graphical way of diagonalizing the
stress matrix (well, it only works in 2D where the tensor is of rank 2).

-Ed 

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