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!

Calculating the radius of a nucleus of a Pd-118 atom

  1. Jun 9, 2006 #1
    Here is the question I am attempting to solve :

    A proton or neutron has a radius r of roughly 110-15 m, and a nucleus is a tightly packed collection of nucleons. Therefore the volume of the nucleus, (4/3)R3, is approximately equal to the volume of one nucleon, (4/3)r3, times the number N of nucleons in the nucleus: (4/3)R3 = N(4/3)r3. So the radius R of a nucleus is about N1/3 times the radius r of one nucleon. More precisely, experiments show that the radius of a nucleus containing N nucleons is (1.310-15 m)N1/3. What is the radius of a palladium nucleus

    So, in order to arrive at an answer I listed variables ,constants and equations that were known:
    R= (N^1/3)*r
    N=(1.3e-15)* (N^1/3)

    and so, in order decrease the number of variables given , I plugged in variables into variables:

    R=(N^1/3)*r ---> R/r =(N^1/3)
    N=(1.3e-15) * (N^1/3) ---> N=(1.3e-15)*R/r

    so I substituted the new expression for N into:

    4/3*pi*r^3 =4/3*pi*R^3 * N ----> 4/3*pi*r^3= 4/3*pi*R^3*((1.3e-15)*R/r):

    pi and 4/3 cancel , show I should be left with:

    r^4/(1.3e-15) = R
    since r = 1e-15 , then R should equal :


    And my answer is no where near the actually answer : Can you tell me what I am doing wrong
  2. jcsd
  3. Jun 10, 2006 #2

    Andrew Mason

    User Avatar
    Science Advisor
    Homework Helper

    So wouldn't the radius of the Pd-118 would be [itex]1.31e-15 * N^{1/3}[/itex] where N is the number of nucleons in the Pd-118 nucleus?

    Last edited: Jun 10, 2006
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?

Similar Discussions: Calculating the radius of a nucleus of a Pd-118 atom
  1. Atomic Nucleus (Replies: 10)