Rajasthan BoardEnglish MediumSTD 12 SciencePhysicsNUCLEI2 Marks
Question
What is nucleus? Give a general introduction.
✓
Answer
→The central part of an atom is called nucleus. The nucleus contains the positive charge of the atom and mass densely concentrated at the centre of the atom. →The dimensions of a nucleus are much smaller than those of an atom. →Rutherford's experiments on scattering of $\alpha$ particles demonstrated that the radius of a nucleus was smaller than the radius of an atom by a factor of about $10^4$. →From this we can say that the volume of a nucleus is about $10^{-12}$ times the volume of the atom. →In other words the atom is almost empty. →If an atom is enlarged to the size of a classroom, the nucleus would be of the size of pinhead. → The nucleus contains most (more than $99.9 \%$ ) of the mass of an atom.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.