Welcome to the NavList Message Boards.

NavList:

A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

Compose Your Message

Message:αβγ
Message:abc
Add Images & Files
    or...
       
    Reply
    Re: New Moon, Perigee, and Solstice
    From: Frank Reed CT
    Date: 2003 Dec 23, 18:25 EST
    Rodney M, you wrote:
    "You can't separate these things as causes. Someone earlier referred to
    the "Q" of electrical tank (RLC) circuits."

    One of the nicest things about modern physics education is that oscillation theory is taught as a generalized topic. So you learn first (usually!) about the general properties of systems with friction, restoring force, and inertia, discover how they behave in resonance and time decay, and later apply them to all the varied resonant phenomena in Nature and in technology.

    And:
    "To say that such an equivalent circuit exists is a very long way from
    being able to write it down. However, local pieces of the circuit, such
    as the Bay of Fundy, may be quite well understood."

    It's one of those things that's worth knowing "in principle", but in practice the details are better done by a full-blown numerical integration.

    "For example, it is apparently known well enough to say that adding some
    R at the top of the Bay, by putting a tide mill there, would tune the
    bay toward resonance, rather than away."

    Ain't science grand?!  :-)

    Related tide trivia: Before the Zuider Zee was dammed in the early 20th century, the government of the Netherlands commissioned the famous physicist of electromagnetism fame, Henrik Lorentz, to work out the changes in the tides that would occur when the dike across the Zuider Zee was closed. There was real concern that large resonances might result following such a big change in the geometry of the coastline. Lorentz and his associates were able to confirm that this would not happen.

    Frank E. Reed
    [X] Mystic, Connecticut
    [ ] Chicago, Illinois
       
    Reply
    Browse Files

    Drop Files

    NavList

    What is NavList?

    Join NavList

    Name:
    (please, no nicknames or handles)
    Email:
    Do you want to receive all group messages by email?
    Yes No

    You can also join by posting. Your first on-topic post automatically makes you a member.

    Posting Code

    Enter the email address associated with your NavList messages. Your posting code will be emailed to you immediately.
    Email:

    Email Settings

    Posting Code:

    Custom Index

    Subject:
    Author:
    Start date: (yyyymm dd)
    End date: (yyyymm dd)