Magnetism

A magnetic field \(\overrightarrow{\mathrm{B}}=\mathrm{B}_{0} \hat{j}\) exists in the region \(a < x < 2 a\) and \(\overrightarrow{\mathrm{B}}=-\mathrm{B}_{0} \hat{j}\), in the region \(2 a < x < 3 a\), where \(\mathrm{B}_{0}\) is a positive constant. A positive point charge moving with a velocity \(\vec{v}=v_{0} \hat{i}\), where \(v_{0}\) is a positive constant, enters the magnetic field at \(x=a\). The trajectory of the charge in this region can be like,