Making use of the uncertainty relation, calculate the energy of the localization of a neutron in a nucleus, i.e. the kinetic energy that a neutron must possess to enter a nucleus. The dimensions of the nucleus are of the order of 10^(-14) m. Isn't there contradiction between this result and the experimental fact that even thermal neutrons with kinetic energies of the order of 10^(-2) eV are able to penetrate the nucleus?

Making use of the uncertainty relation, calculate the energy of the lo

1.	Making use of the uncertainty relation, calculate the energy of the localization of a neutron in a nucleus, i.e. the kinetic energy that a neutron must possess to enter a nucleus. The dimensions of the nucleus are of the order of 10^(-14) m. Isn't there contradiction between this result and the experimental fact that even thermal neutrons with kinetic energies of the order of 10^(-2) eV are able to penetrate the nucleus?
Answer» Solution :The KINETIC energy of the neutron is `Kgeh^(2)//2ma^(2)~~0.2MeV`. It may be seen at first GLANCE that only very FAST neutrons can PENETRATE the nucleus, but this is in contradiction with experiment. However, it should be taken into account that in the nucleus the neutron is not a free particle, but interacts strongly with the other nucleons (nuclear forces). The mean binding energy per nucleon is known to be several mega-electron-volts, which GREATLY exceeds the localization energy calculated above. This enables all the neutrons, including thermal ones, to penetrate the nucleus.

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