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Photon: Day 2, P2
Photon: Day 2, P2
We need a way to inject energy into the system and it would be good if we could do this by injecting photons, so that the kids could observe photon-induced excitation, as well as emission. We need an interface for doing this (a “laser”?) and of course the photon’s frequency (color) has to be controlled by the kid.
Add multiple atoms and introduce the “laser” method for exciting them. (This doesn’t have to be, or look like, a laser – the important point is that the student get to select the atom to be excited and the color of the photon.) The atoms all have initial velocities, so when the model is run they bang into each other.
QX: Would it be a problem if we excite the atoms while the model is running (which seems more natural)?
[Paul Note: that in order to excite the atoms the kids will have to discover that it takes very special photons to do the job – and different photons for the different species of atom.]
[Paul Note: we set up the initial conditions so that such absorption events do happen, and we remind the kids that they can rewind the tape to observe these rare events.]
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org.concord.modeler.text.LineIcon0.94010105<html><body face=Verdana><b>Task: excite all the atoms, then run the model and watch the graph of energies.</b></html>-333301
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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 happening to the energy?
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<body face=Verdana>Can a photon emitted by one atom ever be absorbed by another? If so, is the second atom the same kind as the first, or different?</html>
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org.concord.modeler.text.LineIcon120.025101015<html><center><b><font face=Verdana size=4><a href="photon1.cml">Previous</a></font></center></html>-ff3334
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