Free Charges in a Dielectric Sphere

AI Thread Summary
A dielectric sphere containing free charges can generate a net electric field despite being electrically neutral due to the addition of these free charges. Initially, the sphere is neutral, but when free charges are introduced, they create an electric field both inside and outside the sphere. The discussion clarifies that free charges are not inherent to the dielectric material but are added externally, while bound charges are naturally present within the dielectric. This distinction is crucial for understanding the behavior of electric fields in dielectrics. Overall, the presence of free charges alters the electric field dynamics within the sphere.
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Why is it that a dielectric sphere containing free charges, uniformly distributed throughout, has a net electric field? If the sphere is electrically neutral, then all the charges should cancel out, and since the free charges are uniformly distributed, I don't understand why there should be an electric field inside the sphere.
Thanks
 
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What do you mean? If you say it contains free charges, I think it means that extra charges are added to the sphere because charges of electrons and nuclei are not "free", unless it is in metal. Perhaps I've misunderstood.
 
Sorry about the lack of clarity in my question! It was a reflection of the lack of clarity in my mind.
I think I understand the situation now. The sphere starts off as being electrically neutral, then the free charges are added to the sphere, producing an electric field inside it and outside it.
Am I right in saying that free charges are always added to the dielectric, and the bound charges are always already in the dielectric?
Thanks!
 
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