[meteorite-list] RE: Gravity poll

From: Göran Axelsson <axelsson_at_meteoritecentral.com>
Date: Sun Aug 21 17:01:12 2005
Message-ID: <4308EC3C.1050006_at_acc.umu.se>

I took the only true answer... "you never know"

As the question doesn't contain the necessary information to decide
the outcome of this experiment.

The question was :
"Two same shape spheres (1kg and 10kg) dropped from 100m.
 Which one will reach the Earth's surface faster?"

It's the "same shape spheres" that is the problem. If the shape is
the same (spherical) it doesn't say anything about size. So drag
could be an issue if the size is not the right to compensate.
So depending on the relative size it could be any of the spheres
that reach the ground first.

Nowhere in the question is there any referenses to the density
of the spheres. Even if the size is equal this could make the
experiment fail. If the density is less than the surrounding air
neither sphere will reach the ground.

I rest my case.

  :-)

It reminds me of the story of how to measure the height of
a building with a barometer.
http://www.xs4all.nl/~jcdverha/scijokes/2_12.html#subindex

Nittpickingly yours, G?ran


Matson, Robert wrote:

>Hi All,
>
>The majority of people who have stated that the two spheres will arrive
>at the "same time" are mistaken. The 10-kg sphere will definitely
>arrive first, if only by milliseconds. Now if you had dropped the spheres
>on the Moon, the majority answer would be correct. But wind resistance
>on earth after 100 meters of freefall cannot be discounted, and the
>ballistic coefficient of the denser object is going to come into play.
>
>--Rob
>
>-----Original Message-----
>From: meteorite-list-bounces_at_meteoritecentral.com
>To: Razvan Andrei
>Cc: meteor list
>Sent: 8/21/2005 12:36 PM
>Subject: Re: [meteorite-list] Poll
>
>But, the question was defined, stating spheres of specific weight, in a
>classic physics example. No masses of varying energies or quarkiness,
>just
>good old simple fun to see who would fall for the "what falls faster, a
>pound of feathers, or a pound of lead?"
>
>Mark, lost in a land where most would have said the 10 (whats a kg?)
>would.
>
>
>
Received on Sun 21 Aug 2005 05:03:56 PM PDT