An unstable heavy nucleus at rest breaks into two nuclei which move away with velocities in the ratio of $8:27$. The ratio of the radii of the nuclei (assumed to be spherical ) is
$8 : 27$
$2 : 3$
$3 : 2$
$4:9$
From the statements given below:$(A)$ The angular momentum of an electron in $n^{\text {th }}$ orbit is an integral multiple of $h$.$(B)$ Nuclear forces do not obey inverse square law.$(C)$ Nuclear forces are spin dependent.$(D)$ Nuclear forces are central and charge independent.$(E)$ Stability of nucleus is inversely proportional to the value of packing fraction.
Choose the correct answer from the options given below :
A nucleus represented by the symbol ${ }_{Z}^{ A } X$ has
The mass of a neutron is the same as that of
In the following reaction $_{12}M{g^{24}}{ + _2}H{e^4}{ \to _{14}}S{i^X}{ + _0}{n^1},X$ is
Mass numbers of two nuclei are in the ratio of $4: 3$. Their nuclear densities will be in the ratio of