posted by Mandaleigh on .
A conducting spherical shell with a total charge of +12.6 micro-coulombs has a point charge of -3.6 micro-coulombs placed at its center. The negative point charge will push the electrons in the spherical shell away from it. This will leave the inner shell with positive charge and the outer shell with an excess of electrons. These charges on the inner and outer shell are known as the induced charge. How much charge (in total) is induced on the outer radius of the shell in micro-coulombs?
Hint: this can be done using Gauss' law. First draw a Gaussian inside the shell (between the inside and outside radius). Regardless of the nature of this conductor it's still a conductor and therefore has a definite electric field which was mentioned in class. With the field known, the flux through the Gaussian can easily be found which allows an easy calculation of the total charge enclosed by the Gaussian. With this one can find the charge on the inside surface. With some thought, the outside charge can be found (without using Gauss' law).