# Electric field on a point around a finite wire

1. Apr 4, 2015

### flivon

1. The problem statement, all variables and given/known data
In the figure below, there is a linear rectilinear uniform wire with charge density of $\lambda$. It its located at the Z axis, where z1 = a and z2 = b, (b> a)
The point O is the origin of the coordinates. "R" is the cylindrical polar radial coordinate.

a) Find the $\vec{E}(\vec{r})$ in the point P
b) Determine the angulus between $\vec{E}(\vec{r})$ and the polar versor $\hat{r}(\varphi )$

2. Relevant equations
Gauss Law maybe?
$\oint_S {E dA = \frac{1}{{\varepsilon _0 }}} Q$

3. The attempt at a solution
I honestly dont have any ideia on how to solve this. Do you guys know some material where I can find something similar?

2. Apr 5, 2015