Respostas

2014-07-08T14:48:10-03:00
8 μC  ~> 8.10⁻⁶ C

E = KQ/d²

18x10^3 = 9.10⁹ . 8.10⁻⁶  / d²

d² =  72 .10³ / 18.10³


d= √ 4  = 2 m




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