Summary of Mass Concepts and Formalisms
In classical mechanics, mass has a central role in determining the behavior of bodies. Newton's second law relates the force F exerted in a body of mass m to the body's acceleration a:
- .
Additionally, mass relates a body's momentum p to its linear velocity v:
- ,
and the body's kinetic energy K to its velocity:
- .
In special relativity, relativistic mass is a formalism which accounts for relativistic effects by having the mass increase with velocity.
Since energy is dependent on reference frame (upon the observer) it is convenient to formulate the equations of physics in a way such that mass values are invariant (do not change) between observers, and so the equations are independent of the observer. For a single particle, this quantity is the rest mass; for a system of bound or unbound particles, this quantity is the invariant mass. The invariant mass M of a body is related to its energy E and the magnitude of its momentum p by
where c is the speed of light.
Read more about this topic: Mass
Famous quotes containing the words summary, mass and/or concepts:
“I have simplified my politics into an utter detestation of all existing governments; and, as it is the shortest and most agreeable and summary feeling imaginable, the first moment of an universal republic would convert me into an advocate for single and uncontradicted despotism. The fact is, riches are power, and poverty is slavery all over the earth, and one sort of establishment is no better, nor worse, for a people than another.”
—George Gordon Noel Byron (1788–1824)
“the melodious but vast mass of today’s
Writing ...”
—John Ashbery (b. 1927)
“Once one is caught up into the material world not one person in ten thousand finds the time to form literary taste, to examine the validity of philosophic concepts for himself, or to form what, for lack of a better phrase, I might call the wise and tragic sense of life.”
—F. Scott Fitzgerald (1896–1940)