There is current flow I in the z direction (along z-axis) which will produce circular magnet field.

There is another current i along x direction initially ($i<), the direction of thos current can be adjusted with slider.

The magnet force between current segment, $i d\vec{\ell}$ in magnetic field $\vec{B}=\frac{\mu_o I}{2\pi r}\hat{\theta}$ is $d\vec{F}=i d \vec{\ell}\times \vec{B}$

The direction of current is represented with red arrow. Gray arrows are magnetic field, Blue arrows are interaction force.

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