Complete Question
A thin, horizontal, 12-cm-diameter copper plate is charged to 4.4 nC . Assume that the electrons are uniformly distributed on the surface. What is the strength of the electric field 0.1 mm above the center of the top surface of the plate?
Answer:
The values is [tex]E =248.2 \ N/C[/tex]
Explanation:
From the question we are told that
The diameter is [tex]d = 12 \ cm = 0.12 \ m[/tex]
The charge is [tex]Q = 4.4 nC = 4.4 *10^{-9} \ C[/tex]
The distance from the center is [tex]k = 0.1 \ mm = 1*10^{-4} \ m[/tex]
Generally the radius is mathematically represented as
[tex]r = \frac{d}{2}[/tex]
=> [tex]r = \frac{0.12}{2}[/tex]
=> [tex]r = 0.06 \ m[/tex]
Generally electric field is mathematically represented as
[tex]E = \frac{Q}{ 2\epsilon_o } [1 - \frac{k}{\sqrt{r^2 + k^2 } } ][/tex]
substituting values
[tex]E = \frac{4.4 *10^{-9}}{ 2* (8.85*10^{-12}) } [1 - \frac{(1.00 *10^{-4})}{\sqrt{(0.06)^2 + (1.0*10^{-4})^2 } } ][/tex]
[tex]E =248.2 \ N/C[/tex]
