Final answer:
J.J. Thomson's plum pudding model describes an atom as a sphere of uniform positive charge with electrons embedded within it. This historical model has been surpassed by more advanced atomic theories.
Step-by-step explanation:
Thomson's nose rule is not a recognized scientific principle or concept. Instead, you are likely referencing to J.J. Thomson's atomic theory, in which he discovers electrons and proposes the plum pudding model of the atom. According to this model, the atom is composed of electrons that were thought to reside within a sphere of uniform positive charge, similar to plums within a pudding or raisins within a loaf of bread. This model was proposed before the discovery of the proton or neutron and has since been replaced by more accurate atomic models.