$A$ neutrino is a particle which:

Two nuclei have their mass numbers in the ratio of $1: 3$. The ratio of their nuclear densities would be

Give one example each of central force and non-central force.

The mass number of a nucleus is

Assume that protons and neutrons have equal masses. The mass of a nucleon is $1.6 \times 10^{-27} \ kg$ and the radius of a nucleus is $R = 1.5 \times 10^{-15} A^{1/3} \ m$. The approximate ratio of the nuclear density to the water density is $n \times 10^{13}$. The value of $n$ is $.................$

The mass number of an iodine nucleus and a polonium nucleus is $125$ and $216$ respectively. The ratio of the radius of the iodine nucleus to that of the polonium nucleus is: