Potential Difference in spherical shell

[feedmeister]

Homework Statement

Figure 16.69
A thin spherical shell made of plastic carries a uniformly distributed negative charge -7e-10 coulombs (indicated as -Q1 in the diagram). Two large thin disks made of glass carry uniformly distributed positive and negative charges 1.7e-05 coulombs and -1.7e-05 coulombs (indicated as +Q2 and -Q2 in Figure 16.69). The radius R1 of the plastic spherical shell is 7 mm, and the radius R2 of the glass disks is 4 meters. The distance d from the center of the spherical shell to the positive disk is 19 mm.

(a) Find the potential difference V1 - V2. Point 1 is at the center of the plastic sphere, and point 2 is just outside the sphere.
volts
(b) Find the potential difference V2 - V3. Point 2 is just below the sphere, and point 3 is right beside the positive glass disk.
volts

Remember that the sign of the potential difference is important.

Homework Equations

E = (Q/A)/E_o

The Attempt at a Solution

I tried calculating the field from the capacitor and multiplying it, but I really think I'm going in circles. Anyone help?

I'm so confused on how to begin... Please help.

 

[WolfpackPride]

I also really need help with this problem. Any help?

 

[yoyoz41]

I also have question on this too can someone help us??