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Homework Help: Radiometric Dating Equation Clarification

  1. Jan 11, 2006 #1
    Hey guys,

    I'm doing this assignment where I'm supposed to come up with an equation that models a certain collection of data. I have 40 sets of points and when graphed, they obviously show exponential decay. Now I've done a bit of research on this topic and the Equation used to calculate the number of particles left is y=A*2^(-x/halflife) where:

    y is the number of particles left
    A is the initial number of particles
    x is time and it increments

    Now i've been trying to come up with this equation by using a general exponential equation and solving for constants. My general equation is y=A*B^kx where A, B, and k are constants.

    Am i approaching this problem correctly? My task is to somehow come up with the correct equation which incorporates halflife. I want to somehow prove that the real model for the data is y=A*2^(-x/halflife) which i know is the correct model. How can i go about proving this?

    Here is a bit more information about decay and the above equation is there:

  2. jcsd
  3. Jan 11, 2006 #2
    Dont know if this helps: From an earlier post:

    Here is a graph of the decay. At the very left side the tree has just died. They know about how much C14 is in it at that time. My measuring how much C14 is in it years after, you can approx its age. You measure this by counting how many disintigrations per minuit per gram are occuring.

    http://www.physlink.com/Education/As...ges/ae403a.gif [Broken]

    PHP Code:

    use this site for the math

    Last edited by a moderator: May 2, 2017
  4. Jan 11, 2006 #3
    the first link you posted does not work...
    http://www.physlink.com/Education/As...ges/ae403a.gif [Broken]
    Last edited by a moderator: May 2, 2017
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