| MadSci Network: Physics |
Thanks for your questions!
1. What type of laser(gas) makes a green beam?
Many gases will lase in the green. Helium-Neon lasers will work in the green, as will Argon Ion lasers.
2. How much power would it take for a laser to burn through a business card(or so) with a single pulse.
It will take quite a bit of power to burn through a card in a single pulse. If you use a several-watt laser, you can burn a card in a few seconds, so a 100 Joule pulse ought to make a nice black mark, if not a hole! If you focus the beam, you will need a much less energetic pulse.
3. I was reading about this laser 'gun' that made a short intense laser pulse and charged for 30 seconds!, i thought capacitors only charged for millionths on a second, please explain why this is so.
You can charge a capacitor for as long as you like, depending on the current you supply it and the voltage you can allow to develop on it. To develop a large voltage at small currents could easily take 30 seconds or longer.
-Greg Billock
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