Nuclear Force

Two protons are separated by $10 \mathrm{\AA }$. Let $F_n$ and $F_e$ be the nuclear force and electrostatic force between them, so

Two nucleons are at a separation of $1\times 10^{-15}m$. The net force between them is $F_1$, if both are neutrons, $F_2$ if both are protons and $F_3$ if one is a proton and other is a neutron. In such a case

Two protons are kept at a separation of 40$Å$. $F_n$ is the nuclear force and $F_e$ is the electrostatic force between them. Then

Select the true statement from the following. Nuclear force is

${\mathbf{F}}_{pe }$ represents electrical force on a proton due to an electron, and ${\mathbf{F}}_{\mathbf{e}\mathbf{p}}$ represents electrical force on an electron due to a proton in a hydrogen atom. Similarly, ${{\mathbf{F}}^{\mathbf{\text{'}}}}_{pe }$ represents the gravitational force on a proton due to an electron, and ${{\mathbf{F}}^{\mathbf{\text{'}}}}_{ep}$represents the corresponding force on an electron due to a proton. Which of the following is not true?

Two nucleons are at a separation of $1 \mathrm{fm}$. The net force between them is $F_1$ if both are neutrons $F_2$ if both are protons and $F_3$ if one is a proton and the other is a neutron.

$\text{Fpp, Fnn}$ and $\text{Fnp}$ are the nuclear forces between proton-proton, neutron-neutron and neutron-proton respectively. Then relation between them is

Two nucleons are at a separation of one Fermi. Protons have a charge of $+1.6\times {10}^{-19}\mathrm{C}.$ The net nuclear force between them is $F_1\text{,}$ if both are neutrons, $F_2\text{,}$  if both are protons $F_3\text{,}$ if one is proton and the other is neutron, Then :