A cylinder of radius R= cm 1.2 and length L= 51 cm has a charge Q=2.3 μC spread uniformly along its surface (and not on its flat ends).
a) Calculate the electric field strength a distance d=4 mm from the cylinder’s surface (not near either end)
b)Calculate the electric field strength a distance D=24 m from the rod
Surface area of cylinder without faces = 2πrL
Volume of cylinder = πr2L
pr/(2ε°) = E
The Attempt at a Solution
My grade 12 teacher never taught us electricity so to lightly put it - I'm screwed (so please bare with me and anything I'm misunderstanding)
if my point charge is d=4 mm from the cylinder then from the CENTER it is actually R+d distance away. (similarly, R+D distance for part b).
Now, I know I don't need to do any integration as the charge is spread uniformly along the surface.
This is where I'm not sure what to do. I know that the surface area of the cylinder without its ends is 2πRL, which is the surface that the charge covers. Do I divide Q by the surface area? or do I find volume and do I create my "Gaussian surface" ie, a cylinder and use the radius R+d or R+D instead of R to find the volume? I don't know where to go from here, if someone could explain this, and some of the physics behind it, it might help clear this up for me for good.