A hydrogen gas tube automatically drops into the gas lamp socket on the left of the screen. The spectrum appears at the top right of the screen.Four of the spectral lines are in the visible spectrum and are colored accordingly. The infra red lines and ultra violet lines appear grey.
Create the energy levels on the energy graph on the right by clicking the "Add Energy Level" button. Change individual energy values by clicking and dragging the level with the mouse from the left of the vertical scale.
Click on an energy level to the right of the vertical scale. With the mouse clicked drag a transition line to any other lower energy level. Release the mouse button only when the lower energy level turns green and a spectral line appears in the trial spectrum just below the real spectrum of the gas. Releasing the mouse button midway causes the energy level to disappear.
Manipulate the energy levels as explained in STEP 2. Add more levels and/or transitions until the trial spectrum matches the real spectrum above.
On the right of the screen directly under the simulated (lower) spectrum window is the zoom scale. The yellow rectangle surronding the scale can be resized allowing you to view parts of the spectrum in more detail. Using your mouse click and drag either the left or right sides of the yellow rectangle to resize the spectrum. The resized spectrum scale will appear in both the real (top) and simulated (lower) spectrum windows.
It is possible to delete an individual energy level or transition. Select the specific energy level or transition by pointing and clicking your mouse curser on the specific energy level or transition arrow. An orange rectangle will then appear around the selected object. Press the Delete key on your key board and the selected object will disappear from the energy level graph. Please note that if you delete an energy level, any transistion to or from that level will also be deleted. You can delete all of the energy levels and transitions from the energy graph by clicking the "Clear All" button.Direct comments to: Chandima Cumaranatunge (programming aspects); Sanjay Rebello (physics content).