WEBVTT
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In this exercise, we have the bomber Siri's,
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which comes. It consists off transitions of the hydrogen
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atom between some initial energy level and why to a
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final one and F equals to two. Okay.
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And in the book, we have a figure that
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has some that shows some of the possible transitions in
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the bomber. Siri's in question A and B.
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We have to work with the the transition that results
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in the emitted photon have having the longest possible wavelength
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among those that are shown in the figure. So
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we'll have to consider. Is that first of all
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before doing any calculations? Ah, noticed that the
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energy of a photon is HC over Lunder. Okay
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. Ah, So if we're looking for the shortest
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, actually, in this case, the longest wavelength
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, we have to look for the the shortest energy
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for the smallest possible energy okay of the Fulton.
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But the energy of a photon that's emitted due to
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atomic transitions is equal to the energy of the in
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issue state miners, the energy of the final state
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. So it's e I minus cf. Okay,
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so this is just gonna call this dhoti. So
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if you're looking for the the smallest difference in energy
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possible. We can look up in the in the
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book and the figure and see which transition results in
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the smallest possible difference in energy. And from a
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figure, it's clear that the transition is it that
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results in the smallest energy is the traditions from N
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I equals 23 to the second, uh, the
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second state. Okay. In that case, the
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energy of the third state is given by minus one
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point 512 electoral votes that could be read from the
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figure and also from the figure have the energy of
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the second state. T two equals two minus 3.401
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electoral votes. Okay, so the energy of the
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Fulton is equal to the three mine. Is it
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true? So this is miners. One went 5
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12 plus 3.401 electoral votes, and this is equal
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to one point AIDS 89 electoral votes. That's the
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energy off the That's the the the energy of the
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longest of the photon that has the longest wavelength among
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those shown in the figure. And then we have
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to calculate the wavelength itself, and the wavelength is
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able to age See, over E hc is 1204
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electoral votes in the meters E is 1.889 and it
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from votes. So Lunda is equal to 656 millimeters
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. Okay, now in question CND we have to
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look for the the transition that will result in the
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Fulton with the shortest wavelength among those in the fear
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. So again, uh, following a similar line
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of thought, as I did in question A for
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the for the wavelength Lambda Lambda to be maximum Ah
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, actually, here to be to be minimum we
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have we won the shortest wavelength, loved the possible
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. Then we want the maximum built A and among
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those in the figure, the maximum of lt happens
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in the transition between the sixth energy level and the
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2nd 1 So the energy of the Fulton Belt is
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just gonna be ah SX minus two. And according
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to the figure, E six is minus 0.3 78
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and e two is minus 3.401 So the difference in
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energy is even by 3.23 electoral votes In question D
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, we have to calculate the wavelength expensively and again
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. The wavelength is a silvery So this is go
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140 and after in gold centimeters divided by the energy
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, which is 3.0 to 3 and it from votes
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. So this is 410 millimeters. Okay, in
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a question E, we have to calculate what is
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the shortest possible wavelength in the bomber. Siri's.
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Okay, um, and notice that, as I
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said before, the energy off the emitted electron is
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just dealt her you wish is the energy of the
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final. I'm sorry. The energy of the initial
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state and I e and E. I am sorry
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. Minus the energy of the second state. Because
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in the bomber series, the final state is always
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a second state. So this is equal to 13.6
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times 1/4 minus one over, and I square.
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Okay, this In order to have this, you
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have to remember that the energy off the energy level
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off the hydrogen atom is minus 13.6 electoral votes,
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divided by and square. Um, and we're looking
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for the shortest wavelength possible. That means that we're
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looking for the greatest difference in energy and the greatest
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difference difference in energy. It happens when the second
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term this year zero It won over and I squared
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zero that iss when? And I tends to infinity
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. Okay, Well, when that happens, the
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energy no t is just 3.4 electoral votes and Lunda
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will be hc over that A and that's just 240
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electoral votes and meters divided by 3.4 left in books
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. This is equal to three hundreds and 70.
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I'm sorry through other in 65 centimeters. Okay,
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this is the lower bound for the for the wavelengths
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of the of the bomber Siri's.