A 10nC point charge is located at the center of a thin spherical shell of radius 8cm carrying a -20nC charge distributed uniformly over its surface. What is the magnitude of the electric field 2cm from the point charge? (picture to follow shortly).

I thought the field inside a conductor was always zero, except in this case, we have a point charge. Shouldn't the field at 2 cm from that point charge be the same as it would if there was no sphere around it? I feel like that's not the right approach.

Should I first calculate E between the point charge and the shell, then from the point...

Question

A 10nC point charge is located at the center of a thin spherical shell of radius 8cm carrying a -20nC charge distributed uniformly over its surface. What is the magnitude of the electric field 2cm from the point charge? (picture to follow shortly).

I thought the field inside a conductor was always zero, except in this case, we have a point charge. Shouldn't the field at 2 cm from that point charge be the same as it would if there was no sphere around it? I feel like that's not the right approach.

Should I first calculate E between the point charge and the shell, then from the point...

anonymous · Answer

... to the new radius and use the difference?

anonymous · Answer

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anonymous · Answer

>.< figured it out. Was a totally dumb decimal error.