
#1
May812, 09:56 AM

P: 404

Hi all,
I have a fundamental question about ( mechanical) stress tensor. Stress tensor a 3x3 tensor whose 9 entries looks "scalars" but in figures, the stress is illustrated by nine "vectors". Does it mean the stress tensors is in fact a 3x3x3 tensor of scalars whose nonzero entries are ignored? 



#2
May812, 10:56 AM

Engineering
Sci Advisor
HW Helper
Thanks
P: 6,386

Stress and strain are definitely 3x3 tensors.
If you mean diagrams of a rectangular block with arrows attached to the faces, the arrows are showing the direction of the forces acting on the face, i.e. the components of ##\sigma \cdot \bf{n}## where ##\bf{n}## is the normal vector to the face. If you meant some other diagram, can you post a link to it? 



#3
May812, 11:37 AM

P: 404

Yes those diagrams that you mentioned. So when they write σ_{11} beside one of the arrows, the arrow is the force component in that defined direction andσ_{11} tells us about "magnitude" of the force. However it seems to be the force per unit area, otherwise the stress must be multiplied by the surface.
Thanks. 



#4
May812, 12:31 PM

Engineering
Sci Advisor
HW Helper
Thanks
P: 6,386

Is stress tensor a 3x3 or 3x3x3 tensor? 


Register to reply 
Related Discussions  
Cauchy stress principle & eigenvalues of stress tensor  Materials & Chemical Engineering  1  
energymomentum tensor: metric tensor or kronecker tensor appearing?  General Physics  2  
The Stress part of the Stress  Energy  Momentum Tensor  Special & General Relativity  6  
Shear stress in Energymomentum Stress Tensor  Special & General Relativity  16  
I can't see how stressenergy tensor meets the minumum tensor requirement  Special & General Relativity  4 