Physics - Magnetism Question with Solution | TestHub

We know that the force on a charged particle $e$ due to a magnetic field is given by
$$\begin{array}{ll}& \vec{F}=e(\vec{v}\times \vec{B})\\ \text{ Here }\vec{v}=v_x=\hat{i}\text{ and }\vec{B}=B_y\hat{j}& \\ \therefore & \vec{F}=e{v}_x{B}_y(\hat{i}\times \hat{j})=e{v}_x{B}_y\hat{k}\end{array}$$ Therefore the subsequent motion of the charged particle will be a circle in the $xz$ plane.