Given the mass of iron nucleus as $55.85\,u$ and $A=56$, find the nuclear density?
$m_{ Fe }=55.85\,u =9.27 \times 10^{-26} \,kg$
Nuclear density $=\frac{\text { mass }}{\text { volume }}=\frac{9.27 \times 10^{-26}}{(4 \pi / 3)\left(1.2 \times 10^{-15}\right)^{3}} \times \frac{1}{56}$
$=2.29 \times 10^{17} \,kg \,m ^{-3}$
The density of matter in neutron stars (an astrophysical object) is comparable to this density. This shows that matter in these objects has been compressed to such an extent that they resemble a big nucleus.
The mass density of a nucleus varies with mass number $A$ as
In helium nucleus, there are
Assertion $(A):$ Forces acting between proton-protn $\left(f_{p p}\right)$, proton-neutron $\left(f_{p p}\right)$ and neutron-neutron $\left(f_{n n}\right)$ are such that $f_{p p} < f_{p n}=f_{n n}$
Reason $(R):$ Electrostatic force of repulsion between two protons reduces net nuclear forces between them.
The force acting between proton and proton inside the nucleus is
An alpha particle is projected towards a stationary ${}_{92}^{235}U$ nucleus with $KE$ kinetic energy find distance of closest approach