Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: The problems with space

  1. Sep 26, 2006 #1
    The problems with space......

    Just pondering how you would measure an object's density when in space or a vacuum.....

    Was thinking attach it to a spring and use the spring constant but would a spring work in an area with a low gravitational field strength?

    What are other people's ideas?
  2. jcsd
  3. Sep 26, 2006 #2


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    You need to apply a known force, then measure the acceleration of the body. You can do this with a spring (if you know the spring constant). It takes some practice but if you can stretch the spring and hold a constant length as the body accelerates you will be applying the needed constant force.
  4. Sep 27, 2006 #3
    do you use the natural frequency of the spring or look at the time period and root mass?
  5. Sep 27, 2006 #4
    a bit confused :s
  6. Sep 27, 2006 #5
    If the object is reasonable in size, insert it in your thermos bottle, then fill the thermos from a bottle filled to a known volume.

    Have 2 of your astronaut friends spin you while you're doing it if you're having trouble poring and stuff.

    Or use a syringe for the purpose instead, and inject water into the thermos till it's full and measure the displacement.
  7. Sep 27, 2006 #6
    As for the mass, use a centrifugal scales.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook