why isn't my bulb glowing when I'm using a bulb of 0.5 watts and a battery of 8 watts?

I'm studying 6th grade and my teacher is not explaining everything. I will get 5 marks if you answer my question as this is a school project. 

2 Answers

  • k w
    Lv 7
    4 weeks ago

    AND what's the amp rating of each ? and is it AC or DC ?

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    • k w
      Lv 7
      4 weeks agoReport

      dc current not likely to light an A/c bulb, if this is real, not fake like many posts are....

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  • 4 weeks ago

    first of all, the important rating of a battery is its voltage, which you left off.

    Equally important is the voltage rating of the bulb, again, which you left off.

    If the two match, the bulb will glow at its full intensity.

    If the battery voltage is lower, the bulb will glow with less intensity

    if the battery voltage is higher, the bulb will glow very brightly but will soon burn out. 

    for example, if you use a 1.5 volt battery (eg AA or AAA or C) and a 120 volt bulb, it will not glow at all. 12 volt battery and 120 volt bulb, same. But a 1.5 volt battery and a 3 volt bulb will glow dimly. 

    Also, if the bulb is not an incandescent type, but a LED, it gets even more complicated. The polarity is important, it will not light at all if the polarity is incorrect, and you need the right voltage AND a series resistor to prevent failure. 

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