. The electrostatic energy of z protons uniformly distributed throughout a spherical nucleus

The electrostatic energy of z protons uniformly distributed throughout a spherical nucleus of radius R is Given by E = 3/5 Z(Z – 1) e²/4πε₀R

The measured masses of the neutron, ¹₁H, ¹⁵₇N and ¹⁵₈O are 1.008665 u, 1.007825 u, 15.000109

u and 15.003065 u, respectively. Given that the radii of both the ¹⁵₇N and ¹⁵₈O nuclei are same,

1 u = 931.5 MeV/c² (c is the speed of light) and e2/(4πε₀) = 1.44 MeV fm. Assuming that the difference between the binding energies of ¹⁵₇N and ¹⁵₈O is purely due to the electrostatic energy, the radius of either of the nuclei is

(1fm = 10^-15 m)

A. 2.85

B. 3.03

C. 3.42

D. 3.80