00:01
Hello, and in this question here, we're asked to determine the energy levels of hydrogen if the coolant force doubled in strength.
00:09
So to do this, we're going to begin by using the same method that bore initially used to calculate energy levels of hydrogen, and the energy, he said, was equal to one -half times mv squared, which is the kinetic energy of the electron minus e -squared over 4 pi e -0 times the radius.
00:30
And this here is the term due to the coolome interaction between the electron and the proton.
00:37
Okay.
00:38
Now if the coolone force was the double in strength, this means the contribution that the coolome, the energy from the coolome interaction would also double.
00:48
So we're multiplying by two.
00:50
And we're going to use this to find out energy levels.
00:53
Now, we're still going to assume that the angular momentum is quantized in terms of mv.
00:58
So the angular momentum, which is mvr, and it's quantized in units of h bar.
01:04
Okay.
01:05
And we also need another condition.
01:08
And because the electron is obeying circular motion around the proton, okay, we're going to say that the force, okay, because of the circular motion, the force is directed radally inwards, and the force is equal to minus mv squared divided by r.
01:24
And this force that is directed circular inwards is the coulomb force.
01:28
And this is equal to minus e squared over 4 pi e0 times r squared.
01:36
Okay? now again, this is what we do normally, but we're now doubling the strength of the coulomb interaction, so we multiply this by two.
01:44
Okay? so we can rearrange these two conditions here to guess that the radius is equal to n hbar divided by m r, it's nv and v squared is equal to e squared divided by 2 pi e0 times the mass times the radius okay so we can calculate that the square root of v so we can take we can get v instead of v squared and this gives this v is equal to e divided by the square root of 2 pi e0 times the mass times r okay so this means we can sub in v into this equation here.
02:35
So i'm going to get that r is equal to n hbar divided by m times the square root of e over 2 pi e0 times m times r.
02:54
Okay.
02:55
Now this skips by simplifying it up, this implies that let me just go down to the next line that r is equal to n h bar times the square root of r times two pi e zero uh two pi e zero divided by e squared um times n okay so what i've actually done here i've said that it's not it's not the numerator divided by e i've included the denominator here inside the square root okay so i've said that it is square root of this.
03:38
Okay? so that's how i get the e squared in the denominator.
03:41
So this implies r is equal to 2 pi e0 divided by e squared times m times h bar squared times n squared...