A positively charged elctroscope near a finger

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When a positively charged electroscope is approached by a finger without contact, the deflection of the leaves will slightly decrease due to the polarization of molecules in the finger, which attracts negative charges and repels electrons in the electroscope. This results in a partial neutralization of the positive charges in the leaves. The discussion raises a question about whether a dipole induced by a conductor can polarize the conductor itself, with the consensus being that the effect would be minimal. Replacing the finger with a neutral conducting metal rod would likely produce a more noticeable effect. Overall, the interaction between the electroscope and the finger demonstrates basic principles of electrostatics and polarization.
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Homework Statement


A positively charged electroscope (with deflected leaves, obviously) is approached by your finger (but not touched). Will the deflection increase, decrease, or remain the same?


Homework Equations


None, purely conceptual


The Attempt at a Solution


I think the effect would be very slight. The electroscope would polarize the mlcls in your finger, causing a net attraction. The neg. charges in your finger near the electroscope woud repel some electrons down into the leaves and partially neutralize the positive charges in the leaves. This will cause the deflection to decrease slightly.

What my question really amounts to is:
Does a dipole induced by a conductor, in turn, polarize the conductor even a little.

Out of curiosity if the finger were replaced by a neutral conducting metal rod what would happen? I know the body is conductive, I'm just not exactly sure if the effect is the exact same in this case.

Thanks!
 
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Well really, you'd need to put your finger bang in the middle to see any effect at all, hmmm, i doubt it would amount to much really, and you're right, if anything the deflection would decrease, and the conductor would be very very partially polarized.

And i think you're right, the effect would be a lot more obvious with a neutral conducting metal rod, an interesting question though! I'm sure someone has seen it before :P
 
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