Volume charge density w/o surface charge density

AI Thread Summary
The discussion revolves around confusion regarding the relationship between volume charge density and surface charge density in Griffiths' electrodynamics. The equation E_{out} - E_{in} = σ_free/ε_0 is referenced, highlighting the behavior of electric fields inside and outside a uniformly charged circular volume. The participant initially questions how a volume charge density can exist without a corresponding surface charge, given the continuity of the electric field at the boundary. Ultimately, they realize their misunderstanding regarding the direction of the electric field normal when applying the 'pillbox' method. The participant concludes by acknowledging their mistake and resolving their confusion.
vikasagartha
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Im confused by a concept i have run across in Griffiths electrodynamics.

E_{out} - E_{in} = \frac{\sigma_{free}}{\epsilon_0}

However, in the case of a uniform, circular charge density,
\vec{E_{in}} = \frac{\rho r}{3\epsilon_0}\hat{r}
\vec{E_{out}} = \frac{\rho R^3}{3\epsilon_0 r^2}\hat{r}

But this electric field is continuous @ r=R. If a volume has a charge density, doesn't it have to have some sort of a surface charge? How can there be no surface charge?
 
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Silly question. Realized my mistake. Sorry. I forgot that the normal to the electric field is in opposite directions when drawing a 'pillbox.' So sorry.

Answered my own question.
 
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