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What generates nuclear energy?
What is the name given to the splitting of an atom?
Nuclear fission.
What do nuclear power plants produce?
Electricity
Does nuclear energy pollute the air with smoke?
No, it does not emit polluting gases.
What comes out of those large towers at the power plant?
Just clean water vapor.
What happens inside a nuclear power plant if the control rods are fully inserted into the reactor?
The fission reaction stops completely because the rods absorb the neutrons.
What is the function of the water that comes into direct contact with the nuclear fuel in the reactor?
To cool the uranium and transfer the generated heat to power the generators.
Why does uranium found in nature need to go through the "enrichment" process?
To increase the amount of Uranium-235, which is the type that actually undergoes fission.
What is the main difference between the Chernobyl (1986) and Fukushima (2011) accidents?
Chernobyl was caused by human error and design flaws; Fukushima was caused by a natural disaster (earthquake and tsunami).
What does the term "half-life" of a radioactive element mean?
É o tempo necessário para que metade da radioatividade daquele elemento desapareça. [1, 2, 3]
Where are Brazilian power plants located and what is their importance?
They are located in Angra dos Reis (RJ). Angra 1 and Angra 2 generate about 2% to 3% of Brazil's electricity, and are essential to guarantee energy for the Southeast region when hydroelectric reservoirs are low.
What are uranium "isotopes" and which one actually generates energy in the power plant?
Isotopes are variations of the same chemical element. The uranium that generates energy is Uranium-235, which is much rarer in nature than Uranium-238.
What is the role of the "moderator" (such as pure water or heavy water) within the reactor?
It serves to reduce the speed of neutrons. Slower neutrons have a greater chance of breaking apart the next uranium atom.
What is a "chain reaction" in nuclear energy?
This occurs when the splitting of an atom releases neutrons that break apart the next atoms, generating a continuous domino effect that produces heat without stopping.
What is the biggest advantage of nuclear energy compared to coal and natural gas?
It does not emit greenhouse gases during operation. Furthermore, a tiny amount of uranium generates the same amount of electricity as tons of coal.
What is the "negative void coefficient"
It is a physical mechanism that causes the reactor to slow down automatically if the water gets too hot and turns to steam, preventing explosions.
What is the "void ratio" that caused Chernobyl to collapse?
This occurs when steam replaces water, increasing the reactor's power output instead of decreasing it.
What is the difference between PWR and BWR reactors?
In a PWR (Powered Water Reduction) system, the core water does not boil; in a BWR (Built Water Reduction) system, it boils and goes directly to the turbine.
What are fast and thermal neutrons?
Thermal power plants are slow (used in conventional power plants); fast ones generate more fuel than they consume.
What is "Xenon Poisoning"?
It is the accumulation of a gas that absorbs neutrons and prevents the reactor from starting up for hours.
How does uranium mining affect the carbon footprint of nuclear energy?
The plant does not emit gases, but the mining, transportation, and enrichment of uranium use fossil fuels, generating a small amount of CO₂.
What is the "Four-Factor Formula" (or Six-Factor Formula) in reactor physics?
The mathematical equation that calculates the neutron multiplication factor (k) in an infinite medium.
What causes instability due to xenon oscillation in very large reactors?
Local changes in neutron flux cause the power to oscillate back and forth in the nucleus.
What is the physical barrier that prevents fusion by magnetic confinement (Tokamaks) from lasting a long time?
The turbulence in the plasma that escapes the magnetic fields destroys the reactor walls.
What is the r-process (fast neutron capture) in nucleosynthesis?
The creation of superheavy elements in collisions of neutron stars and supernovae.