00:01
Okay, so for this problem, we want to get the binding energy for the last neutron in a phosphorus nucleus.
00:09
So i approached this one basically the same way as the example.
00:13
And the book was done.
00:15
I think it's example four.
00:17
So if you don't know to do this, i would just stop and do, and you haven't looked at an example four.
00:22
I would stop there.
00:24
Or i would start there.
00:27
So, yeah, anyway.
00:28
So basically we want to come up with an equation that relates the mass of the nucleus before and after it loses that neutron.
00:38
And so i'm going to denote m32 to mean the mass of phosphorus when a is equal to 32.
00:48
And we know that that mass, we can break it down into the mass of what it would be if it were 31 with a is 31.
00:59
Plus the mass of a neutron, and then we can subtract the binding energy.
01:07
And then if we want to take, so if we want to get the binding energy, then we can just solve this equation for ebinding.
01:15
And then we obtain that it's the am of the phosphorus 31 isotope plus the mass of the neutron, yeah, mass of a neutron minus the mass of what it is when it's 32...