Mean Life of Radioactive Nuclei, Physicists using the radioactive decay equation y=ae^(-kt) call teh number 1/k the mean life of a radioactive nuclues. The mean life of a radon-222 nucleus is about 1/0.18 = 5.6 days. The mean life of a carbon-14 nuclues is more than 8000 years. Show that 95% of the radioactive nuclei originally present in any sample will disintegrate within three mean lifetimes, that is, by time t = 3/k. Thus, the mean life of a nuclues gives a quick way to estimate how long the radioactive of a sample will last.
2007-12-17 14:54:33 · 1 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
In the equation y = ae^(-kt), a is the original number of nuclei. If t = 3/k, we have y = ae^(-3) = a*0.0497 nuclei left, which is 4.97% of the original number of nuclei, meaning that over 95% of the sample has decayed.
2007-12-17 15:00:44 · answer #1 · answered by DavidK93 7 · 0⤊ 0⤋