Help me relearn something please...Electric force due to half circle of radius 'R'

Question

johnweldon1993 · Answer

Find the electric Field due to a half circle of radius R and total charge Q. First estimate by dividing the charge into 5 equal parts...then repeat for 9 equal parts...and finally using integral calc to solve exactly.

johnweldon1993 · Answer

I'm not sure if they mean at the center of said circle...or at some general point (not specific)...and I'm just having some serious mental blocks on how I used to do these...

johnweldon1993 · Answer

No diagram came accompanying the question...but here's mine 
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anonymous · Answer

Hi

anonymous · Answer

Coulomb's Law tells us the force between two point charges. Our variation tells us the Electric field due to a single point charge. What do we do if we have a continuous charge distribution? We can sum up the electric field caused by each tiny, infinitesimal part of the charge distribution. This means an integral over the charge distribution:$$e=kq/r2$$ does that help at all

johnweldon1993 · Answer

Yeah I know Coulombs Law...

So basically when I break it up into 5 equal parts...

Q = Q/5

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For sake of simplicity lets call those even lol...

Lets move from there...