The central part of an atom or nucleus, has a diameter of about 10-15
m or 1.6 fm in the case of a proton in light hydrogen while 15 fm for a heaviest atom like Uranium.
Nucleus is much smaller than the size of an atom and in the case of Uranium it is 23,000 times smaller than Uranium atom and the nucleus of hydrogen atom is 145,000 times smaller than the diameter of hydrogen atom.
m or 1.6 fm in the case of a proton in light hydrogen while 15 fm for a heaviest atom like Uranium.
Nucleus is much smaller than the size of an atom and in the case of Uranium it is 23,000 times smaller than Uranium atom and the nucleus of hydrogen atom is 145,000 times smaller than the diameter of hydrogen atom.