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Geogebra Plugin
I created a plugin to embed Geogebra files since the current Geogebra plugins are all too old and don't work. See here for general Geogebra embedding instructions.
This is my first plugin and a bit of a cheat: I basically took the Color plugin and modified it until it did what I needed. However, there's still a lot of code that I don't really understand and a few features that are missing.
Here's how I installed it:
The syntax is:
{{ggb>path/to/geogebrafile.ggb 740,300}}
Note that at the moment, if a path is used, it must use /
instead of :
. The default dimensions are 800×400 if they are omitted.
Here's an example from one of Ham Basics pages showing how different waves add and what SWR looks like:
Wave Addition
When two waves overlap, they add up together at every point. Here, the blue and green waves are generated and add up together to form the red wave. You can move the blue and green waves and see the result. To convince yourself that the red wave is really the sum of the blue and green waves, look at points A, B, and C. You can move the blue or green waves by sliding their phase (φ and Φ) around. You'll see that point C is always the sum of A and B.
Download waveaddition.ggb
Where do the blue and green waves need to be so that...
- the red wave is the biggest?
- the red wave is cancelled out?1)
If you press the play button on the bottom left corner, you'll see the blue wave travel to the right and the green wave travel to the left. The red wave oscillates up and down but doesn't travel anywhere. This is called a standing wave (SWR). While the animation is running, slowly decrease the amplitude of the reflected wave (B) and you'll see that the red wave (which is what actually makes it to the antenna), starts moving to the right.