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: Basic mass to weigh conversion?

  1. Nov 24, 2008 #1
    Basic mass to weigh conversion???

    Consider a neutron star of mass M = 1.99e+030 kg and a radius of R = 9 km.
    Assuming uniform density, how much would 1.1 cubic centimeters of neutron star material weigh on the surface of the earth?

    2. Relevant equations
    Volume of Sphere = (4/3)pi(r^3)
    density = Mass/Volume
    gravity = 9.81 m/s^2

    First I converted 9km to 9000m, and 1.1cm^3 to .011m^3
    solve for density; (M=1.99e30)/(vol=(4/3)pi(9000^3) = 6.5168e17

    (.011 x 6.5168e17) x 9.81 = 7.0323e16 N

    its not accepting my answer
     
  2. jcsd
  3. Nov 24, 2008 #2

    LowlyPion

    User Avatar
    Homework Helper

    Re: Basic mass to weigh conversion???

    Welcome to PF.

    Maybe you want to check that conversion?
     
  4. Nov 24, 2008 #3
    Re: Basic mass to weigh conversion???

    why thank you... I'm an idiot
     
    Last edited: Nov 25, 2008
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook