I_k = (0, 500)
U_0 = (0.025, 0)
U = Segment(I_k, U_0)
U_v(x) = 390.0 * x^(0.055)
E = Intersect(U_v, U, (0.009873754677365324, 302.524906452419))
U_2 = (0, 302.52491)
I_v = (0.00987, 0)
a = Segment(E, U_2)
b = Segment(I_v, E)