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Homework Help: Smoke alarm sensors

  1. Jan 10, 2006 #1
    hi, me and my friends all help each other with physics, and weve been tolk that in our test next year there will be somthing on senseors so we thought a little project wold further our knowledge!

    So i think im gonna do one on comparing Photoelectric smokealarm sensors to ionization smoke alarms, however i dont know wether it would be enough to do a project on, do any of you guys no what kinda scienific tests i could carry out on them.(i have the school labratory to use) all i can really think of is testing them to see which one is more efficent.

    thank guys. x
  2. jcsd
  3. Jan 10, 2006 #2

    Tom Mattson

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    That sounds like an interesting project in applied physics. I assume you're using a reflected beam with a photosensor as a trigger. You already mentioned efficiency, but remember that you don't want it to be too efficient. You will want to design your detector to trigger only when a minimum degree of obfuscation of the beam occurs. No one wants the smoke alarm to go off whenever they light up a cigarette! You could conduct some research on how much beam obfuscation there would be if there were a small fire in the room with the detector.
  4. Jan 12, 2006 #3
    do you think it would be possible to measure the voltage accross the to plates in a ionization method smoke alarm. when the alpha particles are not being obstructed at all.

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