Energy Conservation
When we had only linear KE or translational KE of
KE = ( 1/2 ) m v2
we found Energy Conservation to be very useful, writing
Ei = Ef
where E is the total energy,
E = KE + PE
the sum of the Kinetic Energy and the Potential Energy.
Now we have an additional form of Kinetic Energy, KErot. Now the total energy must include that as well,
E = KErot + KEtrns + PE
Energy is still conserved, so when we write
Ei = Ef
we are really writing
KErot,i + KEtrns,i + PEi = KErot,f + KEtrns,f + PEf
where we have now written KEtrns to explicitly state "translational KE" or
KEtrns = ( 1/2 ) m v2
As before, energy changes from one form to another but the total energy remains constant.
|
 |
|
|
|
|
|
||
|
|
|||