00:01
So let's say we have hydrogen with the quantum number in, principal quantum number.
00:05
Then our angular momentum number we know can be from zero to n minus one.
00:11
So let's write it zero to n minus one.
00:14
And then we also have our like magnetic quantum number, as it's sometimes called.
00:20
And this can be in the range of negative l to l, something like this.
00:28
And so if you think about it for each state the degeneracy like the number of states we're going to have in total is going to be the sum over l from l equals zero to n minus one like all the possible l values for each value of l there are two l plus one states because this is two l states plus the middle state which is zero so two l plus one so if we do this this is going to be two times the sum of, sorry, l equals 0 to n minus 1 plus, and then we have this one term.
01:00
So this is just going to be basically n, because we have n minus 1 plus an additional term.
01:07
So we've got that...