Two insulated rings, one of slightly smaller diameter than the other, are suspended along their common diameter as shown. Initially the planes of the rings are mutually perpendicular. When a steady current is set up in each of them.

 

An electron experiences a force $\left[\left(4.0\hat{\mathrm{i}}+3.0\hat{\mathrm{j}}\right)\times {\mathrm{10}}^{-13}\right] \mathrm{N}$, in a uniform magnetic field when its velocity is $\left[\left(2.5\times {\mathrm{10}}^7\right)\hat{\mathrm{k}}\right] \mathrm{m} {\mathrm{s}}^{-1}$. When the velocity is redirected and becomes $\left[\left(1.5\hat{\mathrm{i}}-2.0\hat{\mathrm{j}}\right)\times {\mathrm{10}}^7\right] \mathrm{m} {\mathrm{s}}^{-1}$, the magnetic force of the electron is zero. The magnetic field vector $\overrightarrow{\mathit{B}}$ is:

(1) The magnetic field strength may have been increased while the particle was travelling in air
(2) The particle lost energy by ionising the air
(3) The particle lost charge by ionising the air