Isn't there anybody who knows how to solve this problem?

Question

Consider the following arrangement of two conducting hollow spheres with a point charge of Q0 = 4.50 mC at the center. The inner sphere has a radius of 0.011 m and carries a net charge of Q1= -2.90 mC. The outer sphere has a radius of 0.061m and carries a net charge of Q2 = 6.70 mC. **Note: mC stands for microCuolombs. 1 C = 10^6 mC

A) Calculate the magnitude of the electric field at point A located at a distance 0.021 m from the center.

B) Calculate the surface charge density on the outer surface of the outer sphere. Neglect the thickness of the sphere.

http://i36.photobucket.com/albums/e12/lilbac2003/HollowSpheres.gif

Answer 1

A) Calculate the magnitude of the electric field at point A

located at a distance 0.021 m from the center.

At point A

E=k*q/r^2

E= (9*10^-3)*(4.5-2.9)/(0.021^2) = 32.65 N/C

B) Calculate the surface charge density on the outer surface

of the outer sphere. Neglect the thickness of the sphere.

surface charge density:D

D=10^-6*(4.5-2.9+6.7)

/(4*3.14159*0.061^2)

= 1.775*10^-4 C/m^2 "answer"

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