Respostas

2013-07-29T16:21:15-03:00
Pela formula temos:

E=k*|Q|/d²

7,2*10^-6 = 9*10^9 * Q / (5*10^-1)^2

7,2*10^-6 * 25*10^-2 = 9*10^9 Q

180*10^-8 = 9*10^9 Q

Q = 180*10^-8 / 9*10^9

Q = 20 * 10^-17

Q = 2 *10^1 * 10^-17

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Q = 2*10^-16 C
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