A spherical shell of radius 9.0 cm carries a uniform surface charge density $\sigma$ = 9.0 nC/m².The electric field at r = 9.1 cm is approximately A)zero B)1.0 kN/C C)0.65 kN/C D)0.32 kN/C E)0.13 kN/C

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The electric field $E$ at a distance $r$ from the center of a uniformly charged spherical shell of radius $R$ and surface charge density $\sigma$ is given by $E = \frac{\sigma}{\varepsilon_0} $ for $r > R$, where $\varepsilon_0$ is the vacuum permittivity ($8.85 \times 10^{-12} \, C^2/N \cdot m^2$). Given $\sigma = 9.0 \, nC/m^2 = 9.0 \times 10^{-9} \, C/m^2$ and $r = 9.1 \, cm > R = 9.0 \, cm$, we calculate $E$ as follows:$$E = \frac{\sigma}{\varepsilon_0} = \frac{9.0 \times 10^{-9}}{8.85 \times 10^{-12}} \approx 1.0 \times 10^3 \, N/C$$Therefore, the electric field at $r = 9.1 \, cm$ is approximately $1.0 \, kN/C$.

A Spherical Shell of Radius 9 σ\sigmaσ = 90 NC/m2

A Spherical Shell of Radius 9 $\sigma$ = 90 NC/m²