Re: Work - impulse

In article <1145710165.715899.189460@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>, "Peter" <Poakfield@xxxxxxx> writes:
Mike, I do not disagree that a force orthogonal to the displacement
vector does no work. What I say is that when one object collides with
another object of different mass at rest, and the incident object stops
on impact, momentum is conserved, but kinetic energy (work) cannot
possibly be conserved, even when no permanent deformation of the
objects occurs, and there is no friction or other causes of energy
loss. This is because momentum is a linear function of velocity, but
kinetic energy (work) is a quadratic function. This can occur when a
point mass, like a puck, collides with an extended object, like a
lever, where angular momentum is conserved. This means the same amount
of work = F dot x can result in different amounts of kinetic energy
(work), which shows there is something wrong with the definitions of
work.

Did it occur to you that, perhaps, there is something wrong with your
understanding here?

Mati Meron | "When you argue with a fool,
meron@xxxxxxxxxxxxxxxxx | chances are he is doing just the same"
.

Relevant Pages

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