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Why do we call a zero watts bulb as it so?

  1. Sep 22, 2011 #1
    why do we call a zero watts bulb as it so??

    a zero watts bulb is common in houses,commonly called as 'night lamp'.., if v say it as zero watts lamp., then is it conducts zero current or zero voltage???
    what is the power consumption by modern led lamps and by other fluorescent lamps??
     
  2. jcsd
  3. Sep 22, 2011 #2

    DaveC426913

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    Re: why do we call a zero watts bulb as it so??

    I have never heard of a zero watt bulb.

    Night lights around here use as much as 4 watts.
     
  4. Sep 22, 2011 #3

    jim hardy

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    Re: why do we call a zero watts bulb as it so??

    i'm going to guess it's another dishonest marketing ploy.
    the wattage is a small enough that it rounds to nearest integer value of zero.

    take for example a 30 milliamp LED that drops 3.5 volts

    it'll dissipate 3.5 X 0.03 = 0.105 watt.

    Nearest integer is zero.

    Int(0.105) = 0.

    the capacitor that sets current dissipates no power.

    There's probably a current limiting resistor inside , maybe another 0.1 watt there.

    Put you hand around it. If you can feel ANY warmth it's not zero watts.
    If it were zero watts it couldn't make any light.

    such marketing is an insult.


    old jim
     
  5. Sep 22, 2011 #4
    Re: why do we call a zero watts bulb as it so??

    Soft drink companies discovered that trick long ago. By reporting calories by serving (usually extra small servings) and rounding, diet soft drinks can have zero calories.

    I'm surprised tobacco companies never picked up on that. They could probably say truthfully, "Each cigarette has zero grams of tar or nicotine."
     
  6. Sep 22, 2011 #5
    Re: why do we call a zero watts bulb as it so??

    And anyone with any sense and even minimal knowledge of chemistry would know that "0 Calories" is pretty much impossible for any food product. It doesn't make any sense at all.

    "4 out of 5 X..." and it's big brother "9 out of 10 X..." are overused to the point of cliche, but despite being spoofed in ads now, it'll never go away because people suck at statistics and anything remotely scientific. They know it and take advantage of it.

    There's a fine line between "marketing" and "lying", just fine enough for marketers to ignore it and feign ignorance. (Or worse, even when caught red-handed in a bald faced lie, "free speech")
     
  7. Sep 22, 2011 #6
    Re: why do we call a zero watts bulb as it so??

    You don't get light for no power. Even the LED that I use for night night draw power.
     
  8. Sep 22, 2011 #7

    cmb

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    Re: why do we call a zero watts bulb as it so??

    It's pedantery on behalf of either the vendors, the legislative requirements for advertising these things, or a combination thereof.

    It's a bit like a peperoni sausage snack sold here in UK called 'peperami': Its ingredients include 150% pork!

    (The regulations stipulate that %age content listed is; mass input of ingredients/mass of product. As peperami is made from dried pork, so it weighs less than the pork ingredients that went in.)
     
  9. Sep 23, 2011 #8

    DaveC426913

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    Re: why do we call a zero watts bulb as it so??

    Well, pretty sure Diet Cola is composed of nothing metabolizable. OK, I guess the few mg of colouring and flavoring might count form something.

    There's a line? :tongue:
     
  10. Sep 23, 2011 #9
    Re: why do we call a zero watts bulb as it so??

    well!! it's the gimmick used in sme places..,
     
  11. Sep 23, 2011 #10
    Re: why do we call a zero watts bulb as it so??

    They don't say 0.00 Calories or even 0.0 Calories, they're saying 0 Calories - 1 significant digit. Now if they said 0 calories, there may be an issue.
     
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