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Homework Help: Converting Slugs to Newtons

  1. Oct 7, 2004 #1
    I am working a Physics problem where the mass is given as 20 slugs. To obtain Newtons can I just multiply 20 slugs x (14.59 kg/1 slug) x 9.80 m/s^2 = 2859.64N?
     
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  3. Oct 7, 2004 #2

    Gokul43201

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    Yes, that's right ! :smile:

    Make sure it is the mass that is described as 20 slugs, because slug is also a unit of force itself !! :eek:
     
  4. Oct 7, 2004 #3

    Doc Al

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    Careful. Since a slug is a unit of mass, not force, you can't "convert" slugs to newtons. But if you are trying to find the weight of a 20 slug mass, then you are fine. (Your conversion of slugs to kilograms is correct.)
     
  5. Oct 7, 2004 #4
    So is the mass of a slug 1lb.? And if so, to obtain (mass x gravity) in the U.S. Customary System would it just be 1 x 32 ft/sec^2 to obtain its weight?
     
  6. Oct 7, 2004 #5

    Doc Al

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    In the "British Engineering" System, the unit of mass is the slug and the unit of force is the pound. (Yes, sometimes the pound is also used as a unit of mass--but in my opinion, this is a bad idea in a physics course. 1 pound mass = 0.45359237 kg) The weight of a 1 slug mass is given by W=mg = (1 slug) (32 ft/s^2) = 32 pounds (approximately) as you noted.
     
  7. Oct 7, 2004 #6
    Thank you. It's very confusing but your last explination worked and resulted in a correct answer. I hate it when I get the Free body diagrams right, setting up the 2 equations with two unknowns right, and missing the correct answer due to conversion errors. Again...thank you for your help.
     
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