It is, by definition, never conserved. Its formal study is known as tribology. Bagnold's law describes it for granular surfaces. Coefficients generally denoted with mu indicate its magnitude; the two most important varieties 
It is, by definition, never conserved. Its formal study is known as tribology. Bagnold's law describes it for granular surfaces. Coefficients generally denoted with mu indicate its magnitude; the two most important varieties are static and dynamic. For 10 points—identify this source of energy loss in moving systems.
It is, by definition, never conserved. Its formal study is known as tribology.
FRICTION