{\large\displaystyle \begin{array}{l}e\cdot B\cdot v\,\,=\,\frac{{{m}_{e}}\cdot {{v}^{2}}}{r}\,\,\,\,\,\,\,\left| :v \right.\\\\e\cdot B\,\,\,\,\,\,=\,\frac{{{m}_{e}}\cdot v}{r}\,\,\,\,\,\left| :{{m}_{e}}\,\,\left| :B \right. \right.\\\\\frac{e}{{{m}_{e}}}\,\,\,\,\,\,\,=\,\,\frac{v}{B\,\cdot \,r}\,\,\,\,\,\,\,\,\,\,Einsetzen\,\,von\,\,v\,\,(1)\\\\\frac{e}{{{m}_{e}}}\,\,\,\,\,\,\,\,=\,\,\frac{\sqrt{\frac{2\cdot e\cdot {{U}_{B}}}{{{m}_{e}}}}}{B\cdot \,r}\,\,\,\,\,\,quadrieren\\\\\frac{{{e}^{2}}}{{{m}_{e}}^{2}}\,\,\,\,\,\,=\,\frac{2\,\cdot \,e\,\cdot \,{{U}_{B}}}{{{m}_{e}}\,\cdot {{B}^{2}}\,\cdot \,{{r}^{2}}}\,\,\,\,\,\left| :\,\frac{e}{{{m}_{e}}} \right.\\\\\,\,\,\frac{e}{{{m}_{e}}}\,\,\,\,\,=\,\,\frac{2\,\cdot \,{{U}_{B}}}{{{B}^{2}}\,\cdot \,{{r}^{2}}}\end{array} }