Atomic radius and electrons because opposite charges attract, and more protons creates a stronger charge. The greater attraction draws the electrons closer to the protons, decreasing the size of the particle. Therefore, atomic radius decreases. Down the groups, atomic radius increases. This is because there are more energy levels and therefore a greater distance between protons and electrons. In addition, electron shielding causes attraction to decrease, so remaining electrons can go farther away from the positively charged nucleus. Therefore, size (atomic radius) increases. The following table summarizes the main phenomena that influence the atomic radius of an element: The electrons in the
Particle-beam weapon Particle-beam weapon A particle-beam weapon uses a high-energy beam of atomic or subatomic particles to damage the target by disrupting its atomic and/or molecular structure. A particle-beam weapon is a type of directed-energy weapon, which directs energy in a particular and focused direction using particles with miniscule mass. Some particle-beam weapons have potential practical applications, e.g. as an antiballistic missile defense system for the United States and its cancelled Strategic Defense Initiative. The vast majority, however, are science fiction and are among the most common weapon types of the genre. They have been known by myriad names: phasers, particle accelerator