Vis Viva is the principle that the difference between the aggregate work of the accelerating forces of a system and that of the retarding forces is equal to one half the vis viva accumulated or lost in the system while the work is being done.
The Vis Viva Equations
Let a mass m be in orbit about a mass M. Let the velocity of m be v when it is at a distance r from M and let a be the semi-major axis of the orbit. Then set the kinetic energy equal to the gravitational potential energy to obtain
In the history of science, visviva (from the Latin for living force) is an obsolete scientific theory that served as an elementary and limited early formulation of the principle of conservation of energy.
was held by the rival camp to be the conserved visviva.
Visviva now started to be known as energy, after the term was first used in that sense by Thomas Young in 1807.
It is the direct result of the law of conservation of energy, where the sum of kinetic and potential energy is constant as a satellite moves about its orbit.
Visviva is an historic term in the history of mechanics but it survives in this sole context.
It represents the principle that the difference between the aggregate work of the accelerating forces of a system and that of the retarding forces is equal to one half the visviva accumulated or lost in the system while the work is being done.
Feeds |
Contact