A spherically symmetric charge distribution produces the electric field E=(200/r)r(hat)N/C, where r is in meters.
a) what is the electric field strength at 10cm?
b)what is the electric flux through a 20cm diameter spherical surface that is concentric with the charge distribution?
c)How much charge is inside this 20cm diameter spherical surface?
The Attempt at a Solution
question a is pretty straightforward:
part b is where I get stuck, here's my attempt:
∫E⋅dA=Qenclosed/ε0, Qenclosed is just some charge distribution so let's say we know it and keep it in its variable form, Qenclosed.
since the 20cm diameter spherical surface we drew is a known shape (spherical) we can use it as a gaussian surface?
E4πr2=Qenclosed/ε0→E=KQenclosed/r2. Clearly I see the problem of having two unknowns here.
I guess the problem says nothing about what the dimensions of the "spherical symmetric charge distribution" is... maybe this comes into play?
Just had an idea:
The problem states what the electric field goes as
so for part b:
E=(200/.1m)N/C, our r for part b is the radius of the 20cm concentric spherical surface is 10cm→.1m
If this is correct then part c should be easy:
we just solved for fluxφe