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Excitation and deexcitation: Day 1, P1
Let there be light!
It's all about energy levels...
The reason everything slowed down on the previous page is that the photons were leaving the container. Photons are particles of light, and light is a form of energy. When the photons leave, each one carries away a certain amount of energy -- the energy it took to excite the atom in the first place -- so the system loses energy and the atoms slow down.
If atoms can emit photons do you think they can absorb them, too? Run the model and observe closely what happens.
Note: the energy diagrams should show indicate which state their respective atoms are in. I don't know how to make them do this, but I think it's possible.
Did you notice that the brown atom gets excited by these photons but the yellow atom doesn't?
Do you know why? Can you change the yellow atom so that it will get excited too? Try it first without clicking on the Hint button. If you mess things up, hitting Reset will get you back to normal.
What do you think will happen if you change the energy diagram of the brown atom?
What happens if you change both the ground state and the excited state?
What if you add energy levels to the atoms?
There's only one way to find out. Experiment and see!
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Remember that the energy levels of the atoms are editable.
<p>
You can change either the excited state or the ground state.
<p>
See if you can get the yellow atom to absorb photons by changing only its ground state.
Hint
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What did you have to do to get these photons to excite the yellow atom?
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Make its energy level the same as the brown atom's.
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