1. What is the binding energy per nucleon? Why is the binding energy per nucleon, rather than per nuclide, used to compare nuclide stability?
2. When a nucleus forms from nucleons, is energy absorbed or released? Why?
3. Many scientists reacted skeptically to Einstein's equation E=mc2. why?
http://en.wikipedia.org/wiki/Binding_energy
http://en.wikipedia.org/wiki/Nuclear_binding_energy
http://hyperphysics.phy-astr.gsu.edu/hbase/nucene/nucbin.html
http://www.chem.purdue.edu/gchelp/howtosolveit/Nuclear/nuclear_binding_energy.htm
1. The binding energy per nucleon refers to the energy required to separate the nucleons (protons and neutrons) in an atomic nucleus. It is calculated by dividing the total binding energy of the nucleus by the number of nucleons in that nucleus.
Comparing the binding energy per nucleon is more useful than comparing the absolute binding energy of different nuclides because it allows for a fair comparison between nuclei of different sizes. In larger nuclei, the total binding energy increases due to the presence of more nucleons, but this doesn't necessarily mean that the nucleons are more strongly bound. By dividing the total binding energy by the number of nucleons, we get the average binding energy per nucleon, which gives us an indication of the stability of the nucleus. Nuclei with high binding energy per nucleon are more stable, as it takes more energy to remove or rearrange a nucleon from the nucleus.
2. When a nucleus forms from nucleons, energy is released. This process is known as nuclear fusion. The energy is released because the resulting nucleus has a higher binding energy than the individual nucleons. During the fusion process, nucleons come closer together and become bound by the strong nuclear force. This binding releases energy according to Albert Einstein's mass-energy equivalence principle (E=mc²), where a small amount of mass is converted into a large amount of energy.
3. Many scientists initially reacted skeptically to Einstein's equation E=mc² because it challenged traditional notions of energy and mass. The equation implies that mass and energy are interchangeable forms of the same underlying entity. This concept was different from classical physics, which viewed mass and energy as distinct and unrelated quantities.
Additionally, the equation had profound implications for the understanding of nuclear reactions and the source of the Sun's energy. It suggested that a small amount of matter could be converted into a vast amount of energy, as demonstrated by the atomic bomb and nuclear power.
Einstein's equation was initially met with skepticism because it contradicted some well-established principles of classical physics. However, subsequent experiments and observations provided strong evidence supporting the validity of the equation, and it has since become a cornerstone of modern physics.