${{F}_{21}}=k\frac{\left| {{q}_{1}} \right|\left| {{q}_{1}} \right|}{r_{21}^{2}}\xrightarrow[{{r}_{21}}=a]{{{q}_{1}}=q,{{q}_{2}}=2q}{{F}_{21}}=k\frac{2{{q}^{2}}}{{{a}^{2}}}$

${{F}_{31}}=k\frac{\left| {{q}_{2}} \right|\left| {{q}_{1}} \right|}{r_{31}^{2}}\xrightarrow[{{r}_{31}}=2a]{{{q}_{1}}=q,{{q}_{3}}=-2q}{{F}_{31}}=k\frac{2{{q}^{2}}}{4{{a}^{2}}}=k\frac{{{q}^{2}}}{2{{a}^{2}}}$

${{q}_{1}}$ برایند $F:{{F}_{1}}={{F}_{21}}-{{F}_{31}}=k\frac{2{{q}^{2}}}{{{a}^{2}}}-k\frac{{{q}^{2}}}{2{{a}^{2}}}=k\frac{3{{q}^{2}}}{2{{a}^{2}}}$

${{F}_{12}}={{F}_{21}}=k\frac{2{{q}^{2}}}{{{a}^{2}}}$

${{F}_{32}}=k\frac{\left| {{q}_{3}} \right|\left| {{q}_{2}} \right|}{r_{32}^{2}}\xrightarrow[{{r}_{32}}=a]{{{q}_{3}}=2q,{{q}_{2}}=2q}{{F}_{32}}=k\frac{4{{q}^{2}}}{{{a}^{2}}}$

${{q}_{2}}$ برایند $F:{{F}_{2}}={{F}_{32}}+{{F}_{12}}=k\frac{4{{q}^{2}}}{{{a}^{2}}}+k\frac{2{{q}^{2}}}{{{a}^{2}}}=k\frac{6{{q}^{2}}}{{{a}^{2}}}$

$\frac{{{F}_{2}}}{{{F}_{1}}}=\frac{k\frac{6{{q}^{2}}}{{{a}^{2}}}}{k\frac{3{{q}^{2}}}{2{{a}^{2}}}}=4$