1. Electrostatic Precipitators (Air Pollution Control) Industrial chimneys use high-voltage electrodes to ionize smoke particles. The charged particles are attracted to grounded plates and removed from exhaust gases. Uses: Gauss's law field between plates and charge migration.
2. Photocopiers and Laser Printers A photoconductor drum is uniformly charged. Light discharges specific regions forming a charge image. Toner (oppositely charged) adheres to charged areas and is transferred to paper. Direct application of charge distribution and induction.
3. Capacitors in Electronics Capacitors store energy in circuits — camera flashes (rapid discharge), RAM memory cells, power factor correction in AC circuits. The energy U = ½ formula determines design specifications.
4. Van de Graaff Generator Uses charge transfer by induction to accumulate large potentials (millions of volts). Demonstrates charge on conductors residing only on the outer surface — a direct consequence of E = 0 inside conductors.
5. Lightning Rods (Franklin Rod) A pointed conductor at the top of a building creates a strong electric field (E = σ/ε_{0} at sharp points where σ is large). This ionizes surrounding air, providing a conduction path that safely diverts lightning.
6. Xerography / Inkjet Printing Ink droplets are given controlled charge and deflected by electric fields (like a dipole in an external field) to land on precise positions on paper.
7. Electrostatic Painting / Powder Coating Paint particles are charged and attracted to grounded metal surfaces. Even coverage on complex shapes — directly analogous to field lines terminating on conductors.