Radioactivity and Nuclear Power Essentials

Comprehensive vocabulary flashcards covering basic radioactivity definitions, types of radiation, decay laws, nuclear forces, and the functional components of a nuclear power plant.

Radioactivity

The spontaneous transformation of an unstable nucleus into another more stable nucleus, accompanied by the emission of radiation.

$\alpha$ (Alpha) Radiation

Radiation consisting of helium nuclei ($2^4He$) with a charge of $+2$, where the mass number $A$ decreases by $4$ and the atomic number $Z$ decreases by $2$ during disintegration.

$\beta^-$ (Beta minus) Radiation

Radiation consisting of an electron ($_{-1}^0e$) released when a neutron transforms into a proton, causing the atomic number $Z$ to increase by $1$ while the mass number $A$ remains constant.

$\gamma$ (Gamma) Radiation

An electromagnetic wave with light charge ($0$) emitted when a nucleus releases excess energy, leaving both the mass number $A$ and atomic number $Z$ unchanged.

Radioactive Series

A succession of nuclear disintegrations that leads progressively to a stable nucleus.

Radioactive Activity

The number of disintegrations occurring per second, measured in the unit Becquerel ($1\,Bq = 1\,\text{disintegration/s}$).

Ionizing Power

The capacity of radiation to strip or pull electrons away from atoms.

Irradiation

The state of being exposed to radiation from a source located outside the body.

Internal Contamination

The condition where a radioactive substance has penetrated or entered the interior of the organism.

Demi-vie (Half-life) $T$

The time required for half of the initial radioactive nuclei in a sample to disintegrate and transform.

Decay Constant ($p$)

A constant specific to a radionuclide related to the half-life by the formula $p = \frac{\ln(2)}{T}$, where $\ln(2) \approx 0.693$.

Strong Nuclear Interaction

A very intense attractive force that holds nucleons (protons and neutrons) together inside the nucleus, overcoming the electrical repulsion between protons.

Mass Defect

The difference between the total mass of the individual separated nucleons and the actual mass of the resulting nucleus, which corresponds to released energy.

Mass-Energy Equivalence

The principle expressed by the formula $E = mc^2$, where $c = 3.0 \times 10^8\,m.s^{-1}$, representing how mass converts to energy.

Nuclear Fission

A nuclear reaction where a heavy nucleus, such as Uranium 235, is split into two lighter nuclei, releasing neutrons and energy.

Nuclear Fusion

The process occurring in the Sun and stars where two light nuclei join together to form a heavier nucleus.

Chain Reaction

A self-repeating phenomenon in which neutrons produced by one fission event trigger subsequent fission reactions in other nuclei.

Control Rods (Barres de contrôle)

Components in a nuclear reactor that absorb neutrons to slow down or stop the chain reaction; lowering them slows the reaction while raising them allows it to continue.

Primary Circuit

The circuit that circulates directly through the reactor heart to recover heat from the fission of the nuclear fuel.

Secondary Circuit

The circuit responsible for producing water vapor (steam) to drive the turbine and alternator.

Tertiary Circuit

The circuit that cools the condenser and evacuates excess heat toward the external environment.

Pressurizer

A device used within a nuclear power plant system to manage and maintain pressure.