3.2 gauss’Law This law relates the flux of e thru a closed surface to the charge inside By using this law one can find e of simple charge dis- tributions easily Let a point charge q be at the point P inside the closed surface s. The flux of e thru a small element of area da is E. da Q r1. da Q d o 4丌∈0 4丌∈0 Integrating over yIelds JE da 4丌 4m∈0 4丌∈0