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Any relationship between light from the sun and electricity?

  1. Jan 28, 2009 #1
    I have a Van der Graaff machine here. When I touch it with my finger I get zapped by a big blue spark. Does this spark of light have any relationship or commonality with the light I see all around me from the sun?

    If not, can someone please try to convince me that it does....
    Last edited: Jan 28, 2009
  2. jcsd
  3. Jan 28, 2009 #2


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    When the charge is transferred to your finger (which is more conducting than the insulating band on the Van der Graaff generator) it ionises the air. When the ionized atoms fall back to their original state they emit energy in the form of light.

    In the sun light is produced by a fusion reaction in which two elements merge to a heavier element, which is lighter than the sum of the original elements (i.e. massbefore > massafter). The difference in mass is equivalent to energy (by Einstein's theory of special relativity) which is emitted as light.

    So the commonality is that in both cases we're talking about light, and all light (like radio waves, heat (IR) and UV) consists of photons. I wouldn't really say that they are comparable though, as there are really different causes for both phenomena. May I ask what lead you to asking this question?
  4. Jan 28, 2009 #3
    thanks for the reply and insight. I also posted here if your interested in what they said at yahoo. http://answers.yahoo.com/question/i...W2mUrDqDHQx.;_ylv=3?qid=20090128004037AAFh953

    I am curious because I want to give this Van Der Graaff generator to a friend of the family who is blind. I wanted to give it to him with the understanding that because he can't see; he can still enjoy the energy in a different way. But if someone says its totally different. The sun and the spark are too radically different things, it loses the meaning....I might as well give him a set of stake knives> LOL....
  5. Jan 29, 2009 #4
    Would it be wrong to say. Here is a machine that will zap your senses with energy, just as the sun use to zap your eyes when you could see?

    Kind of poetic I guess, but is it unscientific? Can anyone do better?

    I don't know how to articulate it correctly in regards to scientific definitions. I want to be truthful.
  6. Jan 29, 2009 #5
    There is a sort of tentative relationship if you consider the source of power for your Van de Graaff.If,for example, your power station burns fossil fuels you are re-releasing solar energy that fell on the planet millions of years ago.
  7. Jan 29, 2009 #6


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    I may be strange here, but is it really a good idea to give your friend a Van de Graaff source so that he can zap himself? Can't he just rub himself on some synthetic carpet and then go touch a metal door knob? It is a lot safer!

  8. Jan 29, 2009 #7


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    Definitely poetic, and informally you can say that, yes.

    I don't really see any scientific way to compare the two... they're just totally different manifestations of a very general and undefinable concept called energy.

    I agree with ZapperZ that this would be a good idea if you don't like your friend as much as you pretend.
    Otherwise, if you want your friend to enjoy energy in a way that is less likely to do damage, you should give him a solarium or something :smile:.
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