Calculating Electric Potential and Field for a Charged Disk

[pakman2012]

Homework Statement

2. a) Find the potential due to a continuous charge distribution of a disk with a surface charge, x, at point P.
b) Find the electric field for part A using: attached formula .

Diagram attached.

Homework Equations

attached.

The Attempt at a Solution

Well my first clue was to trying to relate the variables given in the problem and diagrams in relation to potential. I wasn't really able to figure out a way to do so.

 

[member 553083]

For part B, I thought of using the equation given and plugging in the variables from the diagram. However, the angles are confusing me. It would be great if someone could explain how to approach this problem and break it down into steps. Thank you! \begin{align}V(P) &= \frac{1}{4\pi\epsilon_0}\int\frac{\sigma}{r}\,dA\\E(P) &= \frac{1}{4\pi\epsilon_0}\int\frac{\sigma\mathbf{\hat{r}}}{r^2}\,dA\end{align}