Question-Electrostatics-Point charge and uncharged plate

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SUMMARY

The discussion centers on the electrostatic interaction between a point charge and a large uncharged metal plate. It is established that the electric field inside the metal slab is zero, leading to no net force acting on the point charge due to induced charges. However, the concept of the "method of images" is introduced as a standard technique to analyze such scenarios, indicating that the force is non-zero when considering the induced charges on the plate. The confusion arises from the interpretation of forces in relation to the geometry of the system.

PREREQUISITES
  • Understanding of electrostatics principles, specifically Coulomb's Law.
  • Familiarity with the concept of electric fields and charge induction.
  • Knowledge of the "method of images" technique in electrostatics.
  • Basic grasp of boundary conditions in electrostatic problems.
NEXT STEPS
  • Study the "method of images" in electrostatics for complex charge configurations.
  • Explore the implications of induced charge density on conductors in electrostatic equilibrium.
  • Investigate the behavior of electric fields in the vicinity of charged plates and point charges.
  • Learn about the mathematical derivation of forces between point charges and conductive surfaces.
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Students of physics, particularly those studying electrostatics, as well as educators and professionals seeking to deepen their understanding of charge interactions and electrostatic principles.

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Homework Statement


A point charge is placed at a distance "d" from a huge uncharged metal (slab or plate).[Comment: I'm not sure. Work out both cases]. Calculate the force with which the charge attracts the plate.


Homework Equations





The Attempt at a Solution


The field inside the slab is zero. Imagine a plate and a point charge (say +Q) is placed to its right. A negative charge appears on the side facing the charge and positive charge on other side. Calculating the charge density is not a problem. As the field due to plates of charge doesn't vary with distance(they are small compared to the dimensions in this case), there is no net field due to the positive and negative induced charge surfaces at the place where the point charge is. So the point charge won't experience any force. But we were told that the force IS NON-ZERO. For the plate case, the positive and negative induced charges are at the same place and the force is zero. Help!
 
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Sorry. I found that this is a standard example demonstrating some technique called "method of images".
 

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