Uniform magnetic fields of different strengths ( B_1. and. B_2), both normal to the plane of the paper exist as shown in the figure. A charged…

Uniform magnetic fields of different strengths $\displaystyle \left(\mathrm{B}_1\right.$ and $\displaystyle \left.\mathrm{B}_2\right)$, both normal to the plane of the paper exist as shown in the figure. A charged particle of mass m and charge q , at the interface at an instant, moves into the region $\displaystyle 2$ with velocity $\displaystyle v$ and returns to the interface. It continues to move into region $\displaystyle 1$ and finally reaches the interface. What is the displacement of the particle during this movement along the interface ? (Consider the velocity of the particle to be normal to the magnetic field and $\displaystyle \mathrm{B}_2>\mathrm{B}_1$ )