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Ron,
See my replies below.
Gene.
---- Original message ----
>Date: Thu, 13 Mar 2008 01:16:30 -0700
>From: Ron Stone <[EMAIL PROTECTED]>
>Subject: Re: [USMA:40528] revised usage of measures for body mass
>To: [EMAIL PROTECTED]
>
>
>------------
>Metric units are practical and suitable for everyday measures of body mass...
OK
(oftentimes inferred by a measure of weight on a scale*)
Delete this. Even bathroom spring scales are *calibrated* to display body mass
*at a particular location*. Of course, balance scales free of springs measure
mass more directly even though gravitational forces bring the masses into
balance.
>*Mass is oftentimes referenced by a measure of weight on a scale,
Delete this.
>however 'weight' is more specifically the product of a force such as gravity
>that bears on a mass.
This statement is completely false! Delete it.
In a frame of reference other than the surface of the earth, such as the
surface of the moon; the same body mass would experience a weight or force of
gravity that is only about
>1/6 the gravity on the earth. Replace "gravity" by "weight"
>------------
>
>I also like the example you wrote. Would you mind if I include the three
>paragraphs below for purposes of general information handouts?
You may use the example *without* the adulteration to which I objected above.
>
>On 2008 Mar 12 Wed DoY 072, at 09:26, <[EMAIL PROTECTED]> <[EMAIL PROTECTED]
> > wrote:
>
>> A person of 60 kilograms body mass has a weight of about 600 newtons
>> on the surface of the earth.
>>
>> That same person has the same body mass of 60 kilograms on the
>> surface of the moon, but a weight of only 100 newtons on the surface
>> of the moon where the acceleration of gravity is only 1/6 its value
>> on the surface of the earth.
>>
>> All the above is by Newton's Second Law:
>> "weight" is mass times the *local* acceleration of gravity in a
>> specified (or implied) frame of reference, 9.8 meters per second
>> squared on the surface of the earth with respect to the earth.
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