For example, enter the following rows of information which represent rate equations for radioactive decay:
Variable | Initial Value | Rate |
---|---|---|
t | 0 | 1 |
N | 100 | -0.1*N |
The time variable will usually have a rate of unity since dt/dt=1 wtih a starting time of t=0. The second row describes the decay as dN/dt = -0.1N , with the initial number of nuclei set to 100. Ten percent of these particles will decay during every time unit. Time, since it is the first variable entered will appear on the horizontal axis and n will appear on the vertical axis.
Section 2 Exercises:
Use the above physlet to solve the following problems. Clear the system each time you begin a new exercise. The half-lives can be found in an appendix of the text.
dN/dt = P - RN
If the initial number of the new nuclei is zero, what is the expression for the equilibrium number of new nuclei?
The probability of a ^{13}C nucleus absorbing a proton in a (p,n) reaction is 0.001. What nucleus is being produce? What is its lifetime?
A beam of 10^{13} protons/sec is incident upon a sample of ^{13}C. After 10 minutes, how many of the new nuclei have been produced? After an hour?