Laws on under age dating
'' The age can still be determined but you have to be more clever in determining it.One common sense rule to remember is that the number of parent isotope atoms the number of daughter isotope atoms = an unchanging number throughout time.Different isotopes of a given element will have the same chemistry but behave differently in Radioactive isotopes will decay in a regular exponential way such that one-half of a given amount of parent material will decay to form daughter material in a time period called a half-life. When the material is liquid or gaseous, the parent and daughter isotopes can escape, but when the material solidifies, they cannot so the ratio of parent to daughter isotopes is frozen in.The parent isotope can only decay, increasing the amount of daughter isotopes. The number n is the number of half-lives the sample has been decaying.
Here are some points to consider: The gamma ray frequencies and intensities produced by radioactive elements in supernova remnants change in the same predictable way as they do here on the Earth.
That number is also the amount of parent that has decayed (remember the rule #parent #daughter = constant). in the age measurements of less than 100 million years.
The narrow range of ages is taken to be how long it took the parent bodies of the meteorites to form.
When plants absorb carbon-dioxide in the photosynthesis process, some of the carbon dioxide has the carbon-14 atom in the molecule.
Assuming that our atmosphere's composition and the cosmic ray flux has not changed significantly in the last few thousand years, you can find the age of the organic material by comparing its carbon-14/carbon-12 ratios to those of now-living plants.
So the rock is 1 half-life 1 half-life 1 half-life = 3 half-lives old (to get the age in years, simply multiply 3 by the half-life in years).