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Homework Help: Operational State of a Bulb

  1. Dec 6, 2017 #26

    CWatters

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    What I meant was how do you yourself (without any circuitry) know that a light bulb has failed? If you walk into a room and there is no light coming from the bulb does that always mean it's failed?
     
  2. Dec 6, 2017 #27
    Lol is that a trick question? It could be that it hasn't been turned on, been physically broken or isn't connected properly so I'd say no
     
  3. Dec 6, 2017 #28

    CWatters

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    Exactly. So failure = true when the switch is ON and the light is off. However if the light takes a fraction of a second to become bright and be detected by the LDR then the failure signal will briefly be true every time the light is turned on. This might not matter but you asked why a time delay might be required.
     
  4. Dec 6, 2017 #29
    Ahh, I see now. That's helped actually - thanks.

    Can you think of any improvements to the circuit that could be made? Up to now I've said perhaps use a different voltage which can be split more evenly across the circuit
     
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