Energy
The specific orbital energy is negative, and
Thus the virial theorem applies even without taking a time-average:
- the kinetic energy of the system is equal to the absolute value of the total energy
- the potential energy of the system is equal to twice the total energy
The escape velocity from any distance is √2 times the speed in a circular orbit at that distance: the kinetic energy is twice as much, hence the total energy is zero.
Read more about this topic: Circular Orbit
Famous quotes containing the word energy:
“The principle of avoiding the unnecessary expenditure of energy has enabled the species to survive in a world full of stimuli; but it prevents the survival of the aristocracy.”
—Rebecca West (1892–1983)
“The tendencies of the times favor the idea of self-government, and leave the individual, for all code, to the rewards and penalties of his own constitution, which work with more energy than we believe, whilst we depend on artificial restraints.”
—Ralph Waldo Emerson (1803–1882)
“Perhaps catastrophe is the natural human environment, and even though we spend a good deal of energy trying to get away from it, we are programmed for survival amid catastrophe.”
—Germaine Greer (b. 1939)