Electric field of "half" an infinite charged sheet

In summary, the task at hand is to find the electric field at a point (0,0,z) caused by a charged sheet with a charge density of ##\sigma##. The electric field can be calculated using the Coulomb law, which involves a double integral. However, handling the symmetry of x and y at the same time can be complicated, so the integral on the y dimension is done first. The resulting answer is then integrated from ##x=-\infty## to ##x=0##. This involves two integrals, one for the x component and one for the z component, which can be simplified. However, the result obtained is not the same as the given answer of ##\frac{\sigma}{4\
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Homework Statement


A charged sheet with charge density ##\sigma## is described by ##-\infty<x<0,-\infty<y<\infty, z = 0##. Find the electric field at ##(0,0,z)##.

Homework Equations


Electric field of continuous density charged body from the Coulomb law:
$$E = \frac{1}{4\pi \epsilon_0}\int_V\frac{\vec{r} − \vec{r_0}}{|\vec{r} − \vec{r_0}|^3}\rho(\vec{r}')dV'$$

The Attempt at a Solution


First I tried to do a double integral but handling symmetry of x y at the same time seems very messy. So I did integral on y dimension first. It is infinite line of charge with density ##\sigma dx##, and the answer is $$\frac{\sigma dx}{2\pi \epsilon_0\sqrt{x^2+z^2}}$$
Then integrate the answer from ##x=-\infty## to ##x=0##.
What I did is integrate z component and x component separately, and do vector addition and take mod in the very end.
So I ended up with 2 integrals:
x component$$\frac{\sigma}{2\pi \epsilon_0}\int_{-\infty}^{0}\frac{x}{x^2+z^2}dx$$
and z component$$\frac{\sigma}{2\pi \epsilon_0}\int_{-\infty}^{0}\frac{z}{x^2+z^2}dx$$
These integral look reasonably simple, but the result I get is strange, so I guess I am wrong at some point. The first one is ##\frac{ln(x^2+z^2)}{2}##, and the definite integral gives intinity. The second one is ##arctan(\frac{x}{z})## gives ##\frac{\pi}{2}##.
I think this kind of question should have a finite answer and the answer given is $$\frac{\sigma}{4\epsilon_0}$$ which is finite. What went wrong?
 
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Actually never mind, the question asked for z component only, I can't believe I overlooked it and spent 2 hours on this.
 
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1. What is an "electric field"?

An electric field is a region in space where electrically charged particles experience a force. It is created by electrically charged objects and is represented by lines called electric field lines.

2. What is a "half" infinite charged sheet?

A half infinite charged sheet is an idealized model of a charged sheet that extends infinitely in one direction, but has a finite length in the other direction. It is often used in physics equations to simplify calculations.

3. How is the electric field of a half infinite charged sheet calculated?

The electric field of a half infinite charged sheet can be calculated using the equation E = σ/2ε0, where σ is the surface charge density of the sheet and ε0 is the permittivity of free space.

4. What is the direction of the electric field of a half infinite charged sheet?

The electric field of a half infinite charged sheet points away from the sheet on both sides. This means that the electric field lines are perpendicular to the surface of the sheet.

5. How does distance from the sheet affect the strength of the electric field?

The strength of the electric field of a half infinite charged sheet decreases as the distance from the sheet increases. This is because the electric field lines spread out as they move away from the sheet, resulting in a weaker field at a greater distance.

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