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Re: SPRINGS

Thanks for the explanation. You may be surprised that "our
tradition" is to suspend the springs with the narrow end down,
not up. Reason? Because others did it that way. That way of
suspending can be rationalized by observing that the error
made while ignoring the mass of the spring is reduced.

For the cylindrical spring 1/3 of the spring mass (ms) must
be added to the attached mass to predict T accurately (using
the simple textbook formula). The required added mass is
less than ms/3 one way and more that ms/3 the other.

So we have two possible explanations. How do you know
that your (making sense) explanation corresponds to what
actually motivated the designers and that they wanted us to
hung spring with more massive coils up?

Daniel Schroeder wrote:

We have the same kind of springs. The purpose of the asymmetry
is to better insure that all the coils are "open" and active
while the spring is stretched. Hang them with the narrow end
upward; that's the end where the spring is stiffest. The weight
of the spring itself then helps open the stiffer coils, so the
spring opens more uniformly rather than first at the top.