Question

Me ajudem a resolver essa questões

Answer 1

E = k * Q/d^2
7,2 x 10^6 = 9 x10^9 *  Q/0,5^2
7,2 x 10^6 = 9 x10^9 *  Q/0,25
7,2 x 10^6/9 x10^9 = Q/0,25
8 x 10^-4  = Q/0,25
Q = 8 x 10^-4 * 0,25
Q = 2 x 10^-4