P = mg ; m = P/g = 15000/10 = 1500кг.
F = kq1q2/R^2 = (9*10^9*10^-8*10^-8)/(3*10^-2)^2 = 10^-3H = 1мН
P = mg ; m = P/g = 15000/10 = 1500кг.
F = kq1q2/R^2 = (9*10^9*10^-8*10^-8)/(3*10^-2)^2 = 10^-3H = 1мН