Understanding the Relationship Between r & $\hat{r}$ in a Vector Equation

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The discussion centers on the distinction between the displacement vector r and the unit vector $\hat{r}$ in a vector equation related to magnetic fields. The first expression is clarified to be incorrect due to the misunderstanding of the vector components. The correct relationship is established as $\hat{r} = \frac{\vec{r}}{r}$, indicating that $\hat{r}$ is derived from r by normalizing it. The participants emphasize the importance of understanding vector notation in physics equations. Overall, the conversation highlights common confusions in vector analysis within the context of electromagnetic theory.
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I'm not sure I get how:\frac{\mu_{0}}{4\pi}\int_{C}\frac{I(d\vec{l}\times\vec{r})}{r^{3}} = \frac{\mu_{0}}{4\pi}\int_{C}\frac{I(d\vec{l}\times\hat{r})}{r^{2}}

the r is a displacement vector in the first, and in the second it's a unit vector, but why is this so?
 
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The second expression is correct, the first one is not.
 
Sorry, meant to put a cubed there. Fixed
 
There's nothing really to get: \widehat{r} = \frac{ \vec{r} }{r}.
 
I see,another dumb question I asked, sorry for wasting your time...
 
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