(Solved): Find the magnetic field at a point on the central axis of the circle of radius a and carrying a curr ...

Find the magnetic field at a point on the central axis of the circle of radius a and carrying a current I. Calculate the magnetic field at the center of the circle using your result.

Please answer this question by according to electromagnetic field theory

Question is this and there is an answer written but there is no explanations and i think some of the steps are missing.So i didnt understand solution.I hope you will explain this answer by step by step,find missing steps and re answer and explain why .Thanks for your efford

2. (20 puan) Yar?çap? \( a \) olan ve bir \( I \) ak?mm? ta??yan çemberin merkez ekseni üzerindeki bir noktadaki manyetik alan? bulunuz. Buldu?unuz sonucu kullanarak çemberin merkezindeki manyetik alan? hesaplay?n?z. \[ \begin{array}{l} \vec{R}=\vec{a}_{R} z-\overline{a_{r}} a \\ \vec{R} \mid=\left(z^{2}+a^{2}\right)^{1 / 2} \\ \overrightarrow{d l}=\overrightarrow{a_{\phi}} a d \phi \\ x \vec{R}=\overrightarrow{a r} a z d \phi+\overrightarrow{a_{z}} \phi^{2} d \phi \\ \vec{n}=\frac{\mu L}{4 \pi} \int_{0}^{2 r} \vec{a}_{2} \frac{a^{2} d \phi}{\left(z^{2}+a^{2}\right)^{7 / 2}} \\ \vec{B}=\overrightarrow{a_{2}} \frac{H_{0} E a^{2}}{2\left(t^{2}+a^{2}\right)^{3 / 2}} \\ t=0 \Rightarrow \vec{b}_{2}=\vec{a}_{h-1} \frac{\not b_{a} I}{2 a} \\ \end{array} \]