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• Exploring the properites of plasma

  Marcin Wachowiak • 07/29/2018 at 19:59 • 0 comments

  „Musical plasma” – recreating music by plasma

  After connecting the experimental kit to the source of elecrical sound signal ( in our case radio player) and setting the working parameters for the device to maintain stable arc we are able to replay the song. The chosen track is being heard by us straight from the electric arc. A variety of sound is being recreated and delivered to our ears just from the tiny plasma flame. We are able to notice that the speaker does not maintain great powers, although it consumes about 100W of power. The emitted sound is comparably as loud as if it was played from the mobile phone. What is more, we can hear that the music is not perfect as it lacks some lower frequencies. However the “colour” of the tone is a subjective feeling. It is clearly distinguishable that the speaker simply does not produce low frequecy – bass tones. When we try to play certaing kinds of music ex. dubstep ot techno, theyir sounds are completely unrecognizable. The reason why the speaker has such characteristic of produced tones is that the membrane layer role is played by the small plasma flame, which is inable to vibrate  in greater amplitude to move greater amounts of air to properly recreate basses. On the other hand the plasma speaker perfectly recreates the high pitched sounds as the plasma arc has a small inertia, which enalbes it to quiver without significant limits. In this way they may be heard as piercing and sharp.

  Plasma recreates sound due to it’s proper modulation . Depending on the input wave the PWM generator stretches or reduces the time of the output driving signal with a constant frequency and by this process it creates condensation and rarefactions of plasma, which transforms it into condensations and decondensations of air. Those changes of air density, which are defined as sound waves, come to our ears as the sensation of music.

  „Plasma compared to ordinary flame and their interaction”

  Continuing our experiment, without changing anything we place a candle end into the arc. We can observe the quick enlightning of the candle and permeate of elecrical arc and candle flame. The plasma arc is barely seen as it almost disappears in the flame. The light emmited by the flame seems multiplied and the music is played on mostly by the flame.

  The quick ignition suggests that the plasma tunel has a very high temeperature. From literature we are able to tell that in our case the plasma has about 6000K degrees. The addiditonal brightness of light is emmited by the carbon atoms, which set in the plasma area are addiditonally heated so that they emit more light than an ordinary burning candle. We can also suppose that flame is quite similar to plasma: it conducts electricity and has a high temperature. Plasma and flame are quite similar phenomena and are affected by the same physical laws, but we are not able to assert that those two objects are the same. This is because flame has much lower temperature than plasma, although it may not be seen at a first sight. (it is an argumentative case between physicians, in various articles and videos we may come across opposing statements). Huge amount of heat and various was of emitting the energy to environment turn our minds to the great amounts energy stored in plasma. Following the idea we see that after delivering the energy to states of matter they change. Firstly form solid state to fluid, then the to gass which in the end transfroms into plasma. This is why plasma is often called the fourth state of matter and where the great internal energy comes from.

  “Plasma - magnet interaction”

  To examine another property of plasma we need a stable electric arc. In this case we turn off the music signal and perform the experiment. To investigate plasma and magnetic field interaction we slowly move a ferrite magnet toward the plasma flame and observe the effects. While we slowly set position of the...

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