ive got a tracking force gauge that reads nm's

Discussion in 'Hi-Fi and General Audio' started by rob, Nov 17, 2004.

  1. rob

    rob SCHMOOOOKIN

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    whats an nm?
    and how many of them are in a gram?

    thanks,

    Rob.
     
    rob, Nov 17, 2004
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  2. rob

    penance Arrogant Cock

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    nm = newton meter - a measuement of force.
    gram = measurement of weight.
     
    penance, Nov 17, 2004
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  3. rob

    rob SCHMOOOOKIN

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    just donr a google ,
    1.5 gramm = 15 mn.
     
    rob, Nov 17, 2004
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  4. rob

    The Moog

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    Well, that's if you are gonna take gravity to be 10m/s^2 rather than 9.8 :D


    The Moog
     
    The Moog, Nov 17, 2004
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  5. rob

    michaelab desafinado

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    Andy, Nm (newton metres) is a unit of torque, not force. mN (millinewtons) on the other hand is are a unit of force, which is probably what rob meant.

    Grams are units of mass, not force so you cannot directly convert grams to millinewtons. Whichever site said that 1.5grams = 15millinewtons is making the (common) mistake of assuming that grams are a unit of force.

    Force = mass x acceleration . The acceleration of gravity is (roughly) 9.8m/s² so the force of gravity on 1.5grams = 1.5 * 9.8 = 14.7mN (millinewtons not Newtons because were talking about grams, not kilograms).

    So, what you (rob) wanted to know is that the gravitational force exerted on 1.5g = 14.7mN. A guage that reads in mN is actually the correct way to do it.

    Michael.
     
    michaelab, Nov 17, 2004
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  6. rob

    rob SCHMOOOOKIN

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    setting up a turn table is a lot more interesting than i thought it might be eh?
    the tracking force on my cart is 1.5g / 15 mN , had to go to the manufacturers web site for that one.
    another thing i found out , trying to aligne an orfoton omb 10 is a nightmare on an alignment protractor.thers not a straight line on the damn thing to use as a referance point.

    http://www.ortofon.com/html/body_magnetic_technical_data.asp?varenr=0131131
     
    rob, Nov 17, 2004
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  7. rob

    penance Arrogant Cock

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    Micheal, torque is an applied force.
    Newton is an Si unit of force.
     
    penance, Nov 17, 2004
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  8. rob

    michaelab desafinado

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    Yes, torque is an applied force, but it's not strictly speaking a pure unit of force, but we're splitting hairs. 1Nm is the torque resulting from a force of 1N being applied at 90deg to the end of a lever that's 1m long.

    Michael.
     
    michaelab, Nov 17, 2004
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  9. rob

    SCIDB Moderator

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    Hi,

    Mass is the amount of matter in an object. Measured in Kilograms (Kg)

    Weight is the force of gravity acting on an object. Measured in Newton (N)

    Weight = Mass x Gravity. On this plant the gravity = 9.81m/s². It is very often rounded up to 10m/s² in text books. This makes it easier to do calculations.

    The mass of an object will stay the same but the weight will vary depending on the gravity. For example, a lump of lead 10kgs will be 10Kgs on earth & 10kg on the moon. The weight will be 98.1N on Earth & approx 16.35N on the Moon. The Moon gravity is approx a 1/6 of that on Earth.

    Torque is the turning effect of force and is measured in Newton x metres. (Nm).

    mN is a unit of force. This is a 1/1000 of a Newton.

    Some tracking force gauges have scales in mN. Ortofon balances are marked in this way. It is common to equate 1 gram to 10mN.

    It should be 1 gram = 0.00981N or 9.81mN.

    Set your cartridge to the recommendation. For example if it says 2 grams set to 20mN. The adjust by ear and try lower readings or even higher readings. If you have a test record, this will help.


    SCIDB
     
    SCIDB, Nov 17, 2004
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  10. rob

    penance Arrogant Cock

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    Micheal, I think we are meaning the same thing.
     
    penance, Nov 17, 2004
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  11. rob

    PeteH Natural Blue

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    And if your tracking force gauge really does read in nm, then it's probably a slightly finer-grained instrument than you need for the task at hand. And while we're having an anality competition, 9.8 N / kg is enough decimal places for the strength of gravity on Earth unless you're going to specify your altitude above sea level too. ;)
     
    PeteH, Nov 18, 2004
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  12. rob

    michaelab desafinado

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    :ffrc:

    Michael.
     
    michaelab, Nov 18, 2004
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  13. rob

    merlin

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    No wonder WM doesn't do vinyl - it simply wouldn't work where he comes from.

    So an important lesson here. Leave the vinyl behind as you board the shuttle - another amazing claim courtesy of Zerogain!
     
    merlin, Nov 18, 2004
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  14. rob

    Tenson Moderator

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    Brilliant :MILD:
     
    Tenson, Nov 18, 2004
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  15. rob

    I-S Good Evening.... Infidel

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    They don't let you take sharp objects on board anyway.
     
    I-S, Nov 18, 2004
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  16. rob

    stumblin Kittens getting even...

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    And to think, they say people on forums are geeks. Can't think why...
     
    stumblin, Nov 19, 2004
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