Let me add the question ==>
Might different type scales measure T or N?
-----Original Message-----
From: Bob Sciamanda
Sent: Friday, August 14, 2015 2:22 PM
To: Phys-L@Phys-L.org
Subject: Re: [Phys-L] field of an ellipsoidal distribution
Carl wrote:
"The YouTube video neglects a small correction by assuming that N points in
the
radial direction. This is the old question of “which way does a plumb bob
point” on a rotating earth point? . . .
Interesting ... My spin is that the You Tube guy is not thinking of a plumb
bob - he is modeling an object resting on a horizontal table top at the
earth's surface. Then his calculated N is indeed the normal force of the
table top on his test object. In addition there is required a frictional
force from the table top to balance the horizontal component of the
centrifugal force.
For a hanging bob model, the string must supply both components, as a single
tension force (T, not N).
Bob Sciamanda
Physics, Edinboro Univ of PA (Em)
treborsci@verizon.net
www.sciamanda.com