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2. A point charge of +2 µC is located at the center of a spherical shell of radius 0.20 m that has a charge –2 µC uniformly distributed on its surface. Find the electric field

a) 0.1 m from the center.
b) 0.5 m from the center.

User Lorina
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Answer:

Step-by-step explanation:

Since the spherical shell has a net charge of -2 µC, it will create an electric field outside the shell. Within the shell, the electric field is zero due to symmetry.

a) To find the electric field 0.1 m from the center, we can use Gauss's law and consider a Gaussian surface in the shape of a sphere with a radius of 0.1 m centered at the center of the spherical shell. The electric field at a distance r from the center of the spherical shell is given by:

E = kq / r^2

where k is Coulomb's constant (9.0 x 10^9 N*m^2/C^2) and q is the charge enclosed by the Gaussian surface.

In this case, the charge enclosed by the Gaussian surface is the point charge of +2 µC at the center of the spherical shell. Therefore, we have:

E = kq / r^2 = (9.0 x 10^9 N*m^2/C^2) * (2 x 10^-6 C) / (0.1 m)^2 = 1.8 x 10^6 N/C

So the electric field 0.1 m from the center is 1.8 x 10^6 N/C.

b) To find the electric field 0.5 m from the center, we can again use Gauss's law and consider a Gaussian surface in the shape of a sphere with a radius of 0.5 m centered at the center of the spherical shell. The charge enclosed by this Gaussian surface is the sum of the point charge of +2 µC at the center and the charge of -2 µC on the spherical shell. Therefore, we have:

q_enclosed = q_center + q_shell = 2 x 10^-6 C - 2 x 10^-6 C = 0 C

Since there is no charge enclosed by the Gaussian surface, the electric field at a distance of 0.5 m from the center is zero.

So the electric field 0.5 m from the center is 0 N/C.

User Mdurant
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