Respostas

2014-03-22T20:53:26-03:00
Resposta

Q = 2.10⁻⁸C
F = 4.10⁻²N
d = 3cm = 0,03m
q = ?

F = k. \frac{Q.q}{d ^{2} }

4.10 ^{-2} = 9.10 ^{9} . \frac{2.10 ^{-8}q }{0,03 ^{2} }

4.10 ^{-2} = \frac{18.10 ^{1}q }{0,0009}

4.10 ^{-2}  =  \frac{180q}{9.10 ^{-9} }

180q = 9.10⁻⁴.4.10⁻²

180q = 36.10⁻⁶

q = 36.10⁻⁶ /180

q = 0,2.10⁻⁶ C

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