Respuesta :
Given:
The charge is q1 = 9.4 nC
The charge q2 = -2.31 nC
The distance between them is r = 4.94 cm
To find the electric field strength at the midpoint between two charges.
Explanation:
The electric field strength at the midpoint will be the sum of electric field strength due to q1 and q2.
The electric field strength can be calculated by the formula
[tex]E=\frac{kq}{r^2}[/tex]Here, k is the electrostatic constant whose value is
[tex]k=9\times10^9\text{ N m}^2\text{ /C}^2[/tex]The electric field strength due to the charge q1 is
[tex]\begin{gathered} E_1=\frac{kq1}{(\frac{r}{2})^2} \\ =\frac{9\times10^9\times9.4\times10^{-9}}{(\frac{4.94}{2}\times10^{-2})^2} \\ =1.39\times10^5\text{ V/m} \end{gathered}[/tex]The electric field strength due to the charge q2 is
[tex]\begin{gathered} E_2=\frac{kq2}{(\frac{r}{2})^2} \\ =\frac{9\times10^9\times2.31\times10^{-9}}{(\frac{4.94}{2}\times10^{-2})^2} \\ =3.4\times10^4\text{ V/m} \end{gathered}[/tex]The electric field strength at the midpoint will be
[tex]\begin{gathered} E=E_1+E_2 \\ =(1.39\times10^5)+(3.4\times10^4) \\ =173000\text{ V/m} \end{gathered}[/tex]Thus, the electric field strength at the midpoint between the two charges is 173000 V/m
