Re: List Reborn

From: <Geoff>
Date: Wed Oct 19 2005 - 18:13:00 EDT

Christopher,

I understand the logic here but I think Steve was right. Just look at the units of momentum and energy. Change in momentum is actually impact not change in energy. The impact and momentum are units of work. Energy is work in time.

Geoff

Christopher Wright <chrisw@skypoint.com> wrote:

On Oct 18, 2005, at 11:41 PM, Steve McKenzie wrote:

> A momentum change does not necessarily result in a change of energy
> level.

I think it does. Any change in momentum represents a change in velocity or a change in mass, Since kinetic energy varies with both mass and velocity, any change in either represents a change in kinetic energy.

KE = mv^2/2 Æ(KE) = 0.5v^2Æm + mvÆv

Usually mass stays constant so ÆKE = mvÆv In that case the change in momentum = m(v + Æv) - mv = mÆv.
Christopher Wright P.E. |"They couldn't hit an elephant at <a href="/group/PipingDesign/post?postID=dS533Jina2En8T3SrjjfSgf4I-QcWabgVkaoSwPNFi-RXwUJnYBOFj1ovZAwm7cVDy5ZgE6haYlRTg">chrisw@skypoint.com</a> | this distance" (last words of Gen.

.......................................| John Sedgwick, Spotsylvania

1864)
<a href="http://www.skypoint.com/~chrisw/">http://www.skypoint.com/~chrisw/</a>

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[Non-text portions of this message have been removed] Received on Wed Oct 19 18:13:00 2005