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Requirements of a circuit

  1. Feb 18, 2013 #1
    First, please look at the attached image.

    Would the lightbulb light up? Why or why not?

    (I thought that the lightbulb would not light up, but I didn't know why.)

    Attached Files:

  2. jcsd
  3. Feb 18, 2013 #2


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    The light bulb would not light up. You've short circuited the battery, and possibly damaged it. And depending on the wire gauge, you may burn the house down.
  4. Feb 19, 2013 #3


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    it wont light up cuz you have only connected one terminal of the globe
    and as OmCheeto said ... its shorting out the battery

  5. Feb 19, 2013 #4


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    Look carefully at the diagram, please, and notice the rounded tip at the bottom (right side in the diagram). That is one contact of the bulb. The threads where the wire is attached form the second contact. As the others have said, in this diagram the + side of the battery is connected to the - side by the wire, resulting in MAXIMUM current!

    In order for the bulb to light up there must be current passing through one contact, through the filament, and through the other contact. That's what we call a "complete circuit". In the diagram with the one contact not connected it's what's called "open circuit", so, no light.
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