The nuclear force between two neutrons in a nucleus is described roughly by the Yukawa potential U(r)=−U_0*r_0*r*e^(−r/r_0), where r is the distance between the neutrons and U_0 and r_0(≈10^(−15)m) are constants. Calculate the ratio for the force between two electrically charged particles where U(r)=−C/r, with C a constant.