balances

[SSHS KPHOX <kphox@MAIL.CCSD.K12.CO.US>]

PHYS-L@lists.nau.edu writes:
> I prattle that though beam balances measure mass:


Okay I am confused, maybe. Here is what I think:

An equal arm or pan balance must have either a gravity field or
accelerated reference frame in order to work. They will be calibrated in
mass units as both sides have the same "g-factor" and the torques balance.

We cannot calibrate a spring scale in mass units that will work in all
reference frames as the acceleration or strength of the field will change
the elongation of the spring as it achieves equilibrium.

What am I missing?

Thanks

Ken Fox
Science Department Coordinator
IB Physics Teacher
Smoky Hill High School
Aurora, CO
kfox@mail.ccsd.k12.co.us