The Lagrangian is equal to this quantity minus the potential energy.
The Lagrangian is equal to this quantity minus the potential energy. In gravitational systems, the virial theorem guarantees that the average of this quantity is equal to negative one half of the average potential energy. In special relativity, this quantity approaches infinity as the velocity approaches the speed of light.  The rotational variety of this is given by one half times I times the angular velocity squared. FTP, identify this quantity, the energy of motion, that is often equal to one half times the mass times the velocity squared.
The Lagrangian is equal to this quantity minus the potential energy.
the kinetic energy (prompt on “T”)