Practice question

**Electric field** defined as E = F/q₀, force per unit positive test charge, unit N/C or V/m, direction along force on positive test charge. For point charge, E = k q/r² radially outward for q>0. Field lines start on positive and end on negative, density indicates strength. In electrostatic equilibrium, the electric field inside a conductor is zero. If the field just outside had a tangential component, charges would move along the surface, contradicting equilibrium. Thus, the field must be normal to the surface. Substituting values gives Electrostatic equilibrium, which matches expected magnitude for this electrostatic configuration, confirming Coulomb's and Gauss's principles and charge quantization consistency.