All,

Steven received an e-mail from someone about one of the webpages on our site that question the awe with which many view "science."

A serious point was made, starting with, "Consider the momentum of 2 balls of wet clay (A and B) both of equal mass (m) travelling along the same straight line in opposite directions with equal speeds which collide TOTALLY inelastically such that they stick together to become one big lump of clay (and no little bits fall off!). ... "  Quite specific, don't you think? And a particular thing was then claimed.

I replied to it in a serious manner, starting with, "Since the balls of clay are wet and collide head on, it is unrealistic to assume that no water is thrown out by the collision. If only one water molecule is flung out then, despite the composite lump of clay having no velocity, the momentum of the whole system has not remained at zero, but has increased. This increased energy is as a result of the collision. ... "  The questioner's point was thus addressed.

The questioner then changed tack completely with, " Thanks for your reply... the balls of clay was just intended as a simple example... but as you seem to take it seriously then ... ", and went off on a tangent.

It is a great pity that universities do not teach people how to think and reason, rather than teaching them what they must 'teach' others.

Neville 

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