Relativity Energy and Momentum

Relative Momentum

Relative Energy

Important Equations

E = Energy

M = mass

c = Speed of light

V = velocity 

p = momentum

  Another consequence of relativity is a relationship between mass,

energy, and momentum. Note that velocity involves the question of how far you go and how long it takes. Obviously, if relativity affects the way observers view lengths and times relative to one another, one could expect that any Newtonian concepts involving velocity might need to be rethought.

    For example, because of relativity we can no longer simply add velocities to transform from one frame to another like a ball rolling along on a train. (However, for small velocities like we see every day, the differences which comes in because of relativity are much to small for us to notice).

    Further, consider momentum (which in Newtonian mechanics is defined as mass times velocity). With relativity, this value is no longer conserved in different reference frames when an interaction takes place. 

Definition provided by stason.org