Magnetic Field at the center of a sphere magnet

Homework Statement

A sphere magnet of radius a has permanent uniform magnetization, z-axis. So we were trying to find the magnetic field at the center of the magnet in class.

Homework Equations

$j_M(θ)=Msin(θ)$

$dI=j_M(θ)adθ$

circular loop

$r_{loop}=asin(θ)$

The Attempt at a Solution

When using Biot-Savart equation for magnetic field of a ring why do you use*
$R^3=(a^2+z^2)$

$R^3=(r_{loop}^2+z^2)$

for the denominator????

Last edited:

TSny
Homework Helper
Gold Member
When using Biot-Savart equation for magnetic field of a ring why do you use*
$R^3=(a^2+z^2)$

$R^3=(r_{loop}^2+z^2)$