Hi everyone(adsbygoogle = window.adsbygoogle || []).push({});

I just need some help with this question. Its a simple one I'm pretty sure.

1. The problem statement, all variables and given/known data

A solid sphere of radius 3 cm is made from a conductor and has a charge of

+ 4 uC placed upon it. What is the electric field strength 1 mm from the

centre of the sphere?

2. Relevant equations

I think this is relevant equation to this.

E = Q/(4pi eo r^2)

3. The attempt at a solution

Q is (4 X 10^-6)/ ( 4 * pi * (8.8 * 10^-12) * (r^2) )

I am a bit confused about r. Is r just the radius in meter which will be 0.03m or do I have to include 1mm from the center in that case it would be 0.014m?

Please help.

Thanks

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# Homework Help: Electric Field strength of sphere

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