Nuclear Physics Flashcards

Flashcards on Nuclear Physics Concepts

Nucleus

The central part of an atom where the total positive charge and almost the entire mass of the atom are concentrated.

Atomic Number (Z)

The number of protons in the nucleus of an atom.

Mass Number (A)

The total number of neutrons and protons inside the nucleus.

Number of Neutrons

Calculated as Mass Number (A) - Atomic Number (Z).

Nuclear Density

The same for all atoms, meaning the density of the nucleus is constant regardless of the atom.

Nuclear Size

Depends on the mass number (A). The volume of a nucleus is proportional to A, and the radius R = R0(A)^(1/3), where R0 ≈ 1.2 x 10^-15 m.

Atomic Mass Unit (amu)

A unit to measure the mass of an atom, nucleus, or nucleon. 1 amu ≈ 1.66 x 10^-27 kg (based on the mass of C-12).

Isotopes

Atoms of the same element having the same number of protons but different numbers of neutrons.

Isotones

Atoms of different elements with the same number of neutrons but different numbers of protons.

Isobars

Atoms of different elements having the same mass number but different atomic numbers.

Mass Defect (Δm)

The difference between the sum of the masses of all the nucleons (protons and neutrons) and the actual mass of the whole nucleus. Δm = [Zmp + (A-Z)mn] - M_nucleus.

Nuclear Binding Energy (B.E.)

The energy required to separate the nucleons to an infinite distance. B.E. = Δm * c^2.

Binding Energy per Nucleon (B.E./A)

Used to check the stability of a nucleus; a higher value indicates greater stability. Iron (Fe) nucleus is the most stable.

Nuclear Fission

A nuclear reaction in which a heavy nucleus splits into two lighter nuclei of comparable mass, releasing energy.

Nuclear Fusion

A nuclear reaction in which two light nuclei combine to form a heavier nucleus, releasing energy.

Nuclear Force

The force that binds the neutrons and protons together inside the nucleus. It is the strongest fundamental force, independent of charge, and a short-range force.