q_{1}에 의한 E_{1y} \approx +3.6 \times 10^{3}\ \mathrm{N/C} (계산: E_{1} = (8.99 \times 10^{9}) \dfrac{4.00 \times 10^{-9}}{(0.100)^{2}} \approx 3596\ \mathrm{N/C})

q_{2}에 의한 E_{2y}: r_{2}^{2} = \displaystyle (0.200\ \mathrm{m})^{2} + (0.100\ \mathrm{m})^{2} = (\sqrt{0.05\ \mathrm{m}})^{2} .

E_{2} = k_{e} \dfrac{|q_{2}|}{r_{2}^{2}} \approx 360\ \mathrm{N/C}.

E_{2y} = -E_{2} \sin \theta, 여기서 \sin \theta = \dfrac{0.100}{\sqrt{0.05}}.

E_{2y} \approx -(360\ \mathrm{N/C}) \times \dfrac{0.100}{\sqrt{0.05}} \approx -161\ \mathrm{N/C}.

E_{y} = E_{1y} + E_{2y} \approx 3596 - 161\ \mathrm{N/C} \approx 3435\ \mathrm{N/C} \approx +3.4 \times 10^{3}\ \mathrm{N/C}