7 x 10⁻⁹C
Inside the spherical shell, the electric field is zero, but outside the surface of the shell, the electric field (E) is given by;
E = [tex]\frac{kQ}{r^2}[/tex] ----------------------(i)
Where;
k = proportionality constant = 9 x 10⁹Nm²/C²
Q = total charge over the spherical shell
r = the radius of the shell
From the question;
E = 700N/C
r = 0.30m
Substitute these values into equation (i) to get the total charge, Q, as follows;
700 = [tex]\frac{9 * 10^9* Q}{0.3^2}[/tex]
700 = [tex]\frac{9 * 10^9* Q}{0.09}[/tex]
700 x 0.09 = 9 x 10⁹ x Q
63 = 9 x 10⁹ x Q
Solve for Q;
Q = 63 / (9 x 10⁹)
Q = 7 x 10⁻⁹C
Therefore, the total charge is 7 x 10⁻⁹C
