Answer:[tex]E=2.9\times 10^3\ N/C[/tex]
Explanation:
Given
Side of square plate [tex]L=25\ cm[/tex]
distance between plates [tex]d=5\ mm[/tex]
no of electron [tex]n=10^{11}\ electrons[/tex]
electron charge [tex]e=1.6\times 10^{-19}\ C[/tex]
[tex]\epsilon _0=8.85\times 10^{-12}[/tex]
Electric field between plates is given by
[tex]E=\frac{\sigma }{\epsilon _0}[/tex]
[tex]E=\frac{\frac{Q}{A}}{\epsilon _0}[/tex]
[tex]E=\frac{ne}{A\epsilon _0}[/tex]
[tex]E=\frac{10^{11}\times 1.6\times 10^{-19}}{0.25^2\times 8.85\times 10^{-12}}[/tex]
[tex]E=2.9\times 10^3\ N/C[/tex]