Question
Write short note on Nuclear Force.
✓
Answer
→Nucleus contains protons and neutrons, in which there is a coulomb repulsion between protons and protons. However, the proton can not escape from the nucleus. Because to bind a nucleus together there must be a strong attractive force of a totally different kind. It must be strong enough to overcome the repulsion between (the positively charged) protons and to bind both protons and neutrons into the tiny nuclear volume.
→Many features of the nuclear binding force are summarised below :
(i) The nuclear force is much stronger than the Coulomb force acting between charges or the gravitational forces between masses. That's why it holds protons and neutrons in the nucleus.
(ii) The range of the nuclear force is of the order of femtometres. For distances greater than one femtometres this force rapidly decreases to zero.
→This leads to saturation of forces in a medium or a large sized nucleus.
→A plot of the potential energy between two nucleons as a function of distance as shown in figure.
→The potential energy is minimum at a distance $r_0$ of about 0.8 fm .The force is attractive for distance larger than 0.8 fm .
→The force is repulsive for distance less than 0.8 fm .
(iii) The nuclear force between neutronneutron, proton-neutron and proton-proton is approximately the same. The nuclear force does not depend on the electric charge.
→Unlike Coulomb's law or the Newton's law of gravitation there is no simple mathematical form of the nuclear force.
→Many features of the nuclear binding force are summarised below :
(i) The nuclear force is much stronger than the Coulomb force acting between charges or the gravitational forces between masses. That's why it holds protons and neutrons in the nucleus.
(ii) The range of the nuclear force is of the order of femtometres. For distances greater than one femtometres this force rapidly decreases to zero.
→This leads to saturation of forces in a medium or a large sized nucleus.
→A plot of the potential energy between two nucleons as a function of distance as shown in figure.
→The potential energy is minimum at a distance $r_0$ of about 0.8 fm .The force is attractive for distance larger than 0.8 fm .
→The force is repulsive for distance less than 0.8 fm .
(iii) The nuclear force between neutronneutron, proton-neutron and proton-proton is approximately the same. The nuclear force does not depend on the electric charge.
→Unlike Coulomb's law or the Newton's law of gravitation there is no simple mathematical form of the nuclear force.
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