1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Critical radius

  1. Mar 29, 2007 #1
    1. The problem statement, all variables and given/known data

    Cloud droplets begin to form on a population of condensation nuclei as the saturation ratio is gradually increased, with temperature held constant. The nuclei have the same chemical composition but a broad range of sizes. Droplets are activated with radii 0.5 μm when the supersaturation reaches 0.15%. Droplets continue to be activated as the supersaturation is raised to 1%. Solve for critical radius corresponding to a supersaturation of 1%. Also solve for the temperature.



    2. Relevant equations

    S*=critical supersaturation
    S=supersaturation
    r*= critical radius
    r*= (3b/a)^(1/2)
    S*=1+((4a^3)/(27b))^(1/2)
    S=1+(a/r)-(b/r^3)

    3. The attempt at a solution

    What ive done:
    S*=critical supersaturation
    S=supersaturation = .0015
    r= .5
    I plugged into S=1+(a/r)-(b/r^3)
    I solved for a,

    then plugged a into S*=1+((4a^3)/27b))^(1/2)
    then solved r*=(3b/a)^(1/2)

    The right answer .075μm and t+293K- but I cannot get this at all.
     
  2. jcsd
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Can you help with the solution or looking for help too?
Draft saved Draft deleted



Similar Discussions: Critical radius
  1. Ionic Radius (Replies: 2)

  2. Atomic radius (Replies: 1)

  3. Radius of an atom (Replies: 1)

  4. Critical Temperature? (Replies: 2)

  5. Atomic radius (Replies: 6)

Loading...