Half life radioactive dating
Trees undergo spurts in growth in the spring and summer months while becoming somewhat dormant in the fall and winter months.When a tree is cut down, these periods are exhibited in a cross section of the trunk in the form of rings.Two hours is 120 minutes, so that’s six half-lives.
If we start with 100 g of a radioactive substance whose half-life is 15 days, after 15 days 50 g of the substance will remain.
In Tom Clancy's book "The Hunt for Red October," a Russian submarine has a nuclear reactor accident with radiation leakage that forces the crew to abandon ship.
At Three Mile Island and Chernobyl, nuclear power plants released radioactive substances into the atmosphere during nuclear accidents.
Uranium-238 decays by alpha emission into thorium-234, which itself decays by beta emission to protactinium-234, which decays by beta emission to uranium-234, and so on.
The various decay products, (sometimes referred to as “progeny” or “daughters”) form a series starting at uranium-238.