Magnifying glass?

You’ve seen how you can burn things with a magnifying glass and some sunlight before right? Well my question is what would happen if you did that under black light (alone)?

2 Comments

  1. SkateRForeveR
    on February 6th, 2012

    Black light is an incorrect term used for ultra-violet light. Ultra-violet light focused through a magnifying glass would produce some heat, but a great deal less than sunlight.

  2. Fractalfallout
    on February 6th, 2012

    The real problem is that the sources of black light (UV) are so diffuse that even with a large magnifying glass, you don’t get much energy in one spot. And some lenses don’t pass UV. The sun is far away and there are parallel rays (nearly) hitting the lens and forming a tight little spot of IR (heat) and light. Most black light sources on earth are coated filters on incandescent or fluorescent lamps and thus the magnifying glass produces an image of a blob or a line.
    To really see an effect you would need to put a UV filter on a high intensity stage lighting spot light. And then you might only get a brighter area of black light effects like glow in the dark.

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Magnifying glass???

What is that magnifying glass in my messenger window and is there any way I can remove it?

1 Comment

  1. Eli
    on February 6th, 2012

    hi :)
    “LiveWords gives you a simple and convenient way to search on the Web for more information about any topic, word, or phrase that comes up in an IM conversation.

    Just highlight a word or phrase in the message window by dragging with your mouse, and the LiveWords symbol, a purple magnifying glass, will appear next to your selected text. Do a “mouse-over” on that symbol (that is, position your cursor over the symbol without clicking) and a window will open containing links to information and search results on the text you’ve highlighted.”
    http://help.yahoo.com/l/us/yahoo/messeng...

    to disable…
    Messenger > Preferences > LiveWords
    uncheck Enable LiveWords
    click Apply
    click OK

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Magnifying glass?

i would like to buy some magnifying glass for the back of my tank, anyone know were i can buy some for my tank x

2 Comments

  1. matrixmaruda
    on February 6th, 2012

    Look for a”Freznel”(not sure about the spelling),but you can find them in Scientific Supply or surplus mail order books.(like Fisher Scientific) Fresnel? Good luck.—–PeeTee

  2. Kea
    on February 6th, 2012

    try a glass store

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Magnifying glass?

Why, when using a magnifying glass at a distance the object is upside down .Then as you move closer the object turns right side up?

1 Comment

  1. DarkDesire
    on February 6th, 2012

    Because the light is bent from both sides of the lens, and after a certain distance, it flips over (the edges, seen from the side, form an “X”). if you are closer than that focus point, it it not flipped over. Make sense?

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