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- Homework Statement
- A rod has cross sectional area A and mass per unit length \mu. Write down the stress energy tensor inside the rod, when it is under a tension F.

- Relevant Equations
- .

Let's arrange the rod's axis parallel to the z axis.

##T_{00} = A/\mu## (since it represents the energy density)

##T_{03}=T_{30} = \frac{F\sqrt{\mu / F}}{A}## (It represents the flow of energy across the z direction)

##T_{33} = F/A## (pressure)

It seems that ##T_{33}## i have got has the wrong sign, and that ##T_{03} = T_{30}## should actually be zero.

i am a little confused on both cases: Where does the sign at ##T_{33} = (-F/A)## comes from? And why are my reasoning involving ##T_{30}## wrogn?

##T_{00} = A/\mu## (since it represents the energy density)

##T_{03}=T_{30} = \frac{F\sqrt{\mu / F}}{A}## (It represents the flow of energy across the z direction)

##T_{33} = F/A## (pressure)

It seems that ##T_{33}## i have got has the wrong sign, and that ##T_{03} = T_{30}## should actually be zero.

i am a little confused on both cases: Where does the sign at ##T_{33} = (-F/A)## comes from? And why are my reasoning involving ##T_{30}## wrogn?

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