Sunday, September 14, 2008

Fundamemtals: Energy conservation

Two approach:
First approach : List all types involved in the problem .
The total of all types before and after must be the same.
e.g KE 1+PE 1 + EPE 1= KE 2 + PE 2 + EPE 2

Second approach : Then changes must add to be zero . Or any increase must be equal to decrease.
Change in KE + change in PE + change in EPE = 0 .Increase in plus and decrease is minus .

In the event there is heat produced , W=Fd. This heat is produced at the end of the event , add W to the RHS of first approach or add W(plus sign) to second approach.