Energy Transfer model

Welcome, one and all to energy transfer principles.

The formula's used are
Ek: 1/2 m*v^2
Eel: 1/2kx^2
Eg: m*g*h
W: fnet*deltax

Across charts, we use the idea that energy is a closed system, except for Ediss, where once it disappears to, it is gone.
This results in formula's such as
Ek=Eg, where one variable needs to be solved for, or a time concept, or a force present can be used.

The other concept is joules, these principles of energy that when indicated by time(seconds) become watts, and in hours kwhr's.
Across energy transfer, we can use pie charts which are conceptual, to LOL charts which are more precise. One of the necessary factors to remember is that in the system which defines the energy entering or leaving, if we are using earth's gravitational force, it must be included.

If we have a 150 kg skateboarder going at 3 m/s, when friction is negligible, what is his Ek?
Ek=1/2 m*v^2
     = 0.5*150*3^2
     = 675 j

This same skateboarder accidentally goes off a cliff whose height we do not know.
To solve for Height we can use:
Ek=Eg
675j=M*g*h
675j=150*10*h
675j/1500=1500h/1500
h= 0.45 M.

If a spring with a constant K of 115 has 280 j of energy stored, how far was it compressed?
  Eel=1/2kx^2
280j= 0.5*115*x^2
280j=57.5x^2
280j/57.5=(57.5x^2)/57.5
4.87=x^2
x=2.2 m