# Line Charge and Charged Cylindrical Shell

1. Oct 2, 2012

### fede1

1. The problem statement, all variables and given/known data
An infinite line of charge with linear density λ1 = 8.0 μC/m is positioned along the axis of a thick insulating shell of inner radius a = 2.1 cm and outer radius b = 4.6 cm. The insulating shell is uniformly charged with a volume density of ρ = -614.0 μC/m3.
What is Ey(P), the value of the y-component of the electric field at point P, located a distance 6.3 cm along the y-axis from the line of charge?
λ2 for shell = -3.23097 μC/m

2. Relevant equations
E.dA = Q/Epsilon nought
Q=rhow*V in terms of volume charge density
Q=lambda*L in terms of linear charge density

3. The attempt at a solution

I'm guessing you need to use Gauss' law with a cylindrical gaussian surface but I'm not sure how you can determine Q enclosed

2. Oct 2, 2012

### Staff: Mentor

Right.
Take your gaussian cylinder and make it of finite length L. Then you should be able to find the charge enclosed in that volume, using λ and ρ.