The velocity of an electron inside a K shell, or any electron in an atomic orbital, cannot be determined with precision. According to quantum mechanics, the behavior of electrons is described by wave functions, and these wave functions provide information about the probability distribution of finding an electron at different locations around the nucleus.
The K shell, also known as the innermost electron shell, corresponds to the principal quantum number n = 1. Electrons in this shell have the lowest energy levels in an atom. However, the concept of velocity, which implies a well-defined speed and direction, is not applicable to electrons in atomic orbitals. Instead, we use the term "electron cloud" or "electron density" to describe the region of space where the electron is likely to be found.
Quantum mechanics describes electrons in terms of wave-particle duality, meaning they exhibit both wave-like and particle-like characteristics. Therefore, the properties of electrons in atoms, including their velocities, are described using probability distributions and wave functions rather than classical notions of velocity.
It's worth noting that the average velocity of an electron can be calculated based on its kinetic energy and mass, using classical physics equations. However, this average velocity does not provide a complete picture of the electron's behavior within the atomic orbitals, as quantum mechanics governs their behavior.