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Photon: Day 2, P1
Photon: Day 2, P1
Same as page 1 of day 1 except that the atoms can be moved around. In their initial positions, the object ball atom decays before it can bounce off the wall and hit the cue ball atom, and when it decays (emitting a photon, of course) it loses most of its energy so that it can no longer excite the cue. The task is to do just that, though – excite the cue ball atom or explain why you can’t. Actually, it can be done – by moving the object ball atom closer to the wall so that it won’t have time to decay before hitting the cue ball atom – but the important point here is to recognize why that adjustment was necessary: that the excited state of the atoms doesn’t last very long, even if there’s no collision the atoms will emit photons and lose their energy that way. (If the atoms are like flashlight batteries in being able to store energy, they’re also like flashlight batteries in losing their energy – except that they do it all at once.) If the kids do manage to excite the cue ball atom, they will notice that it decays by emitting a photon of a different color.
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Pink Atom
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Green Atom
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Adjust the initial speed (in 1000 m/s)
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Execute MW script
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<html><font size=5><b>Run</b></html>
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Execute MW script
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Reload page
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org.concord.mw2d.models.MolecularModel
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Take a snapshot
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org.concord.modeler.text.LineIcon0.94010105<html><body face=Verdana><b>Task: Try to excite the cue ball atom. (We may need a hint here.)</b></html>-333301
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<html><body face=Verdana>Fill in a snapshot image that proves you have excited the cue ball atom:</html>
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org.concord.modeler.text.LineIcon0.93010105<html><body face=Verdana><b>Questions:</b></html>-333301
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<body face=Verdana>What is new about this model? Why is it hard to excite the cue ball atom?</html>
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<body face=Verdana>What is different about the photons emitted by the two kinds of atoms?
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org.concord.modeler.text.LineIcon120.025101015<html><center><b><font face=Verdana size=4><a href="photon2.cml">Next</a></font></center></html>-3367
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