The smallest known 2 body system is the helium atom, which consists of a nucleus containing 2 protons and 2 neutrons, and 2 electrons orbiting around it.
The size of a 2 body system is determined by the distance between the 2 bodies, which is influenced by the strength of their interaction and their individual masses.
Studying the smallest known 2 body system, such as the helium atom, allows scientists to understand fundamental principles of quantum mechanics and the behavior of particles on a small scale.
The smallest known 2 body system is significantly simpler than other multi-body systems, as it only involves interactions between 2 particles. This makes it an ideal system for studying fundamental principles and simplifying complex systems.
The smallest known 2 body system can change or evolve over time through various processes, such as nuclear decay or electron transitions. These changes can be studied and understood through quantum mechanics principles.