- #1
richengle
- 26
- 1
- Homework Statement
- in an INELASTIC collision, how is momentum conserved, but not energy?
- Relevant Equations
- Cons of Momentum
m1v1+m2v2=m1vs'+m2v2' , if car hits small fluffy object m2, initially v2=0, and v1'=v2' ... so
m1v1=[m1+m2](v2')
but why not energy? Why is there a KElost in Cons of Energy?
Cons of Energy
.5m1v1^2+.5m2v2^2=.5m1v1'^2+.5m2v'2^2 +KElost , and again v2=0, v1'=v2'
.5m1v1^2=.5[m1+m2]v2'^2+KElost
I know you could say deformation, but do you somehow have to take the derrivative of energy [wrt what i dont know] to find a maximum, which is dependent on the initial and final masses and velocities?
m1v1+m2v2=m1vs'+m2v2' , if car hits small fluffy object m2, initially v2=0, and v1'=v2' ... so
m1v1=[m1+m2](v2')
but why not energy? Why is there a KElost?
.5m1v1^2+.5m2v2^2=.5m1v1'^2+.5m2v'2^2 +KElost , and again v2=0, v1'=v2'
.5m1v1^2=.5[m1+m2]v2'^2+KElost
using consv of momentum...
KElost=.5[m1v1^2[1-m1/(m1+m2)] ?
.. and if m1>>m2, this is zero,,, how? Some energy should still be lost?
I know you could say deformation, but do you somehow have to take the derrivative of energy [wrt what i don't know] to find a maximum, which is dependent on the initial and final masses and velocities?
m1v1=[m1+m2](v2')
but why not energy? Why is there a KElost?
.5m1v1^2+.5m2v2^2=.5m1v1'^2+.5m2v'2^2 +KElost , and again v2=0, v1'=v2'
.5m1v1^2=.5[m1+m2]v2'^2+KElost
using consv of momentum...
KElost=.5[m1v1^2[1-m1/(m1+m2)] ?
.. and if m1>>m2, this is zero,,, how? Some energy should still be lost?
I know you could say deformation, but do you somehow have to take the derrivative of energy [wrt what i don't know] to find a maximum, which is dependent on the initial and final masses and velocities?
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