Results 1 to 2 of 2

Math Help - Radioactive Decay

  1. #1
    Newbie
    Joined
    Oct 2009
    Posts
    1

    Radioactive Decay

    If Forty percent of a radioactive substance decays in five years. By what percent does the substance decay each year?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    -1
    e^(i*pi)'s Avatar
    Joined
    Feb 2009
    From
    West Midlands, England
    Posts
    3,053
    Thanks
    1
    Quote Originally Posted by Royster123 View Post
    If Forty percent of a radioactive substance decays in five years. By what percent does the substance decay each year?
    Exponential Decay: N(t) = N_0e^{-\lambda t}

    0.6 = 1e^{-40\lambda}

    \lambda = -\frac{1}{40}ln(0.6)

    <br />
N(t) = 1e^{-\left(-\frac{1}{40}ln(0.6)\right) \times 1)}
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Radioactive decay
    Posted in the Differential Equations Forum
    Replies: 1
    Last Post: February 22nd 2011, 12:45 AM
  2. Radioactive decay
    Posted in the Differential Equations Forum
    Replies: 10
    Last Post: November 11th 2010, 08:57 PM
  3. Radioactive Decay
    Posted in the Pre-Calculus Forum
    Replies: 8
    Last Post: January 28th 2010, 10:18 PM
  4. Radioactive Decay
    Posted in the Advanced Applied Math Forum
    Replies: 1
    Last Post: October 11th 2009, 01:12 PM
  5. Radioactive Decay
    Posted in the Pre-Calculus Forum
    Replies: 1
    Last Post: June 14th 2009, 05:22 PM

Search Tags


/mathhelpforum @mathhelpforum