00:02
Question 47 deals with the idea that we have three different elements that we could potentially use for dating to see how old, something that may you're able to dig up is.
00:16
So in the scenario, we dig up or we consider three different isotopes and see how viable they would be for dating.
00:24
So we have carbon 14, excuse me, uranium 238 and potassium 40.
00:30
I took the liberty of finding out all of their half -lives and displayed them here.
00:35
So we want to know if these isotopes are good for dating the lifetime of the earth, which here is just given as t is 4 .5 times 10 to the 9 years.
00:46
And we want to know if the item that we started with had 10 to the 6 atoms present at the earth's formation.
00:55
And again, how can we determine if any of these are viable? we can look at our decay equation and see how many atoms would be present and if we think it's sufficient amount present currently, then i think it would be a viable method to use as a dating method.
01:13
So starting with our given scenario, if we were to start with 10 ,000, 10 to the 6, sorry, atoms, we multiply the 0 .e the negative lambda, which i don't have, but we do have ln of 2 times times.
01:32
Which we know over the half -life.
01:38
So for each of these elements, i'm going to calculate while i'm going to use this function to calculate how many atoms are present based on each of the different elements half -lives are...