Physics
What is nucleus of an atom? Compare it's size with that of the atom. Name it's constituents. How is the number of these constituents determined by the atomic number and mass number of an atom?
Answer
The nucleus is at the centre of an atom whose size is of the order of 10-15 m to 10-14 m (i.e., 10-5 to 10-4 times the size of the atom). It consists of protons and neutrons.
If Z = atomic number and A = mass number of an atom, then the atom contains,
Number of protons = Z
Number of neutrons = A – Z
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