Question

Let $F_{pp},F_{pn}and{F}_{nn}$ denotes the magnitudes of the nuclear force by a proton-proton, proton-neutron and neutron-neutron respectively. When the separation is 1 fermi, then :

• A. $F_{pp}>F_{pn}>F_{nn}$
• B. $F_{pp}=F_{pn}=F_{nn}$
• C. $F_{pp}>F_{nn}>F_{pn}$
• D. $F_{pp}=F_{nn}<F_{pn}$

Answer 1

The correct option is B $F_{pp}=F_{pn}=F_{nn}$

In any atom, protons and neutrons are packed together in a very small space in the nucleus.

• There must be some force of attraction between these particles to maintain the existence of nucleus.
• The columbic force of attraction is not enough to hold many particles in such a small space, as the repulsion force between protons would render the nucleus highly unstable and tend to disintegration.
• Hence, the force of attraction between nucleons which is stronger than the repulsive force between protons is called as nuclear forces.
• Nuclear forces operate within a small distance around 0.10 fermi only.

So, nuclear forces are charge independent.