Question

Define the nucleus of an atom.

Answer 1

Hint :The atomic nucleus is a compact, compact area at the centre of an atom made up of protons and neutrons that was discovered in 1911 by Ernest Rutherford based on the Geiger–Marsden gold foil experiment of 1909. Dmitri Ivanenko and Werner Heisenberg swiftly devised models for a nucleus made up of protons and neutrons after the neutron was discovered in 1932.

Complete Step By Step Answer:
A positively charged nucleus is surrounded by a cloud of negatively charged electrons that are held together by electrostatic force. The nucleus contains almost all of an atom's mass, with the electron cloud contributing just a little amount. The nuclear force binds protons and neutrons together to create a nucleus. Nuclear physics is the discipline of physics concerned with the study and comprehension of the atomic nucleus, including its composition and the forces that tie it together. Ernest Rutherford's efforts to test Thomson's "plum pudding model" of the atom led to the discovery of the nucleus in 1911. J.J. Thomson had previously discovered the electron. J.J.Thomson reasoned that because atoms are electrically neutral, they must have a positive charge as well. Thomson proposed that an atom was made up of negative electrons randomly spread within a sphere of positive charge in his plum pudding model. Later, with the aid of Ernest Marsden and his research colleague Hans Geiger, Ernest Rutherford designed an experiment involving the deflection of alpha particles (helium nuclei) directed against a thin strip of metal foil. If J.J Thomson's model was correct, he reasoned, the positively charged alpha particles would easily pass through the foil with little deviation in their paths, because the foil should act as electrically neutral if the negative and positive charges are so intimately mixed as to make it appear neutral. Many of the particles were deflected at quite great angles, much to his amazement. Because an alpha particle's mass is approximately 8000 times that of an electron, it became clear that a very strong force was required to deflect the large and fast-moving alpha particles. He concluded that the plum pudding model was inaccurate, and that the alpha particle deflections could only be explained if the positive and negative charges were separated, and the atom's mass was a concentrated point of positive charge. This supported the concept of a nuclear atom with a concentrated positive charge and mass core.

Note :
Neutrons and protons make up an atom's nucleus, which are manifestations of more primitive particles known as quarks, which are kept together by the nuclear strong force in specific stable hadron combinations known as baryons. The nuclear force extends long enough from each baryon to bind neutrons and protons together in the face of the repellent electrical interaction between positively charged protons. The nuclear strong force has a relatively narrow range, and it effectively vanishes just beyond the nucleus's border.