GENERAL KNOWLEDGE

Detailed explanation-1: -Nuclear sizes are expressed in a unit called “Fermi” which is a unit of length equal to 1015 metre(one femtometre), used in nuclear physics. It is similar to the diameter of a proton.

Detailed explanation-2: -So, the nuclear sizes are expressed in a unit named fermi.

Detailed explanation-3: -Roughly, the radii of nuclei vary from 1/10 000 to 1/100 000 of the radii of atoms. While atomic sizes are of the order of 100 pm (10−10 m), the common unit of nuclear size is the femtometer (1 fm = 10−15 m), sometimes referred to as 1 Fermi.

Detailed explanation-4: -We can calculate the size of the nucleus, by obtaining the point of closest approach of an alpha particle. By shooting alpha particles of kinetic energy 5.5 MeV, the point of closest approach was estimated to be about 4×10-14m.

Detailed explanation-5: -The correct answer is Fermi. About Fermi: ‘Fermi’ is a Unit in which Nuclear sizes are expressed. It is a unit of length equal to One Femtometre=1015 meter, used in Nuclear Physics.