91影视

a) The radius of the solid sphere,$\mathrm{r}=10鈥�\mathrm{cm}$

b) The magnitude of the electric field,$\left|\mathrm{E}\right|=3脳{10}^3鈥�\mathrm{N}/\mathrm{C}$

c) Distance of the electric field from the center of the sphere,$\mathrm{r}=15鈥�\mathrm{cm}$

Using the concept of the electric field, we can get the net charge of the sphere by substituting the given values in the given formula.

Formula:

The magnitude of the electric field, $\left|\mathrm{E}\right|=\frac{\mathrm{q}}{4{\mathrm{蟺蔚}}_0{\mathrm{r}}^2}$ (1)

The electric field produced by the unknown charge at points outside the sphere is like the field of a point particle with a charge equal to the net charge on the sphere.

Thus, the net charge on the sphere is given by the equation (1) as follows:

$$\begin{gathered} \left|\mathrm{q}\right|=\left(4{\mathrm{蟺蔚}}_0{\mathrm{r}}^2\right)脳\mathrm{E} \\ =\frac{{\left(0.15\mathrm{m}\right)}^2\left(3脳{10}^3\mathrm{N}/\mathrm{C}\right)}{9脳{10}^9\mathrm{N}.{\mathrm{m}}^2/{\mathrm{C}}^2} \\ =7.5脳{10}^{-9}\mathrm{C} \end{gathered}$$

The field points inward, toward the sphere center, so the charge is negative.

Hence, the value of the net charge isrole="math" localid="1657345115513" $-7.5脳{10}^{-9}\mathrm{C}$ .