An electron and a positron are released $(0,0,0)$ and $(0,01.5 \;R)$ respectively , in a uniform magnetic field $\overrightarrow{B} =B_0 \hat i$, each with an equal momentum of magnitude $P= eBR$ Under what condition on the direction of momentum will the orbit be non- intersecting circles.

Question

$\begin{array}{1 1} \cos \theta > \frac{3}{8} \\ \cos \theta < \frac{3}{8} \\ \cos \theta > \frac{-3}{8} \\ \cos \theta < \frac{-3}{8} \end{array} $