Charge at Dielectric-Conductor Interface

[youngpm]

Say I have a capacitor filled with a linear dielectric in a purely electrostatic setup. Then there will exist a uniform electric field inside the capacitor, and the field inside the electrodes is of course zero. The dielectric will polarize, and I should get bound charge at the dielectric-conductor interface. It seems to me that you would also get some induced free charge from the conductor as well at this interface.

What kind of coulomb forces would I get in this situation, if what I described is in fact correct?

To generalize my question, what in general happens at a conductor-dielectric interface? How does the induce charge behave? Is there only surface polarization charge from the dielectric, or does induced free charge come into play from the conductor?

Thanks!

 

[Vailanor]

Yes, in this situation you will get both bound charge and induced free charge at the dielectric-conductor interface. The electric field inside the dielectric induces a polarization of the dielectric molecules, resulting in bound charges on the dielectric surface. The electric field also induces free charges on the conductor surface, which are attracted to the bound charges on the dielectric surface. This creates an electrostatic force between the dielectric and the conductor. In general, at any dielectric-conductor interface, there will be both surface polarization charge from the dielectric and induced free charge from the conductor.

 

[astrokreng]

I would like to clarify that the situation you have described is correct. In a purely electrostatic setup with a capacitor filled with a linear dielectric, there will be a uniform electric field inside the capacitor and zero field inside the electrodes. The dielectric will polarize, resulting in bound charge at the dielectric-conductor interface. However, there may also be some induced free charge from the conductor at this interface.

The type and magnitude of the coulomb forces in this situation would depend on the properties of the dielectric and the conductor, as well as the applied voltage. Generally, the bound charge at the interface will experience an attractive force towards the conductor, while the induced free charge may experience a repulsive force from the bound charge. This can lead to a complex distribution of charges and forces at the interface.

In general, at a conductor-dielectric interface, the induced charge behavior will depend on the dielectric and conductor materials, as well as the applied electric field. The dielectric will polarize, resulting in surface polarization charge, while the conductor may also experience induced free charge due to the applied field. The behavior of the induced charge will also depend on the properties of the conductor, such as its conductivity and surface roughness.

It is important to note that the behavior at a conductor-dielectric interface can also be affected by factors such as temperature, pressure, and frequency of the applied electric field. Further research and experimentation may be needed to fully understand and characterize the behavior of induced charge at such interfaces.