Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: Oh no! The definition of weight again!



Suppose I weigh an oil drop (of known charge) by using the Millikan
apparatus to read the required levitating electric field? Do I directly
read the force of the drop on the apparatus?

Bob Sciamanda (W3NLV)
Physics, Edinboro Univ of PA (em)
trebor@velocity.net
http://www.velocity.net/~trebor


----- Original Message -----
From: "John Mallinckrodt" <ajmallinckro@CSUPOMONA.EDU>
To: <PHYS-L@lists.nau.edu>
Sent: Friday, May 12, 2000 2:22 PM
Subject: Oh no! The definition of weight again!


On Fri, 12 May 2000, Rick Tarara wrote:
. . .
For someone
standing on a scale, this is still a downward force (since the scale
actually reads the upwards force of the scale) ...

Given the third law, this may be a philosophical point, but I wouldn't
say
that. I would say that the scale can only "read" a force that is exerted
*on* it.
. . .
3) The now introduced definition of weight as the downward force of
an
object on it's support--a contact force.
. . .
I hope I have been consistent in previous discussions in making it clear
that this is my preferred definition of "weight." >
John Mallinckrodt mailto:ajm@csupomona.edu
Cal Poly Pomona http://www.csupomona.edu/~ajm