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Q & A: Powering up a 6 Volt light bulb with batteries

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Most recent answer: 12/22/2014
Q:
I found a light bulb that physically fits my project perfectly, but it is 6V. It's this one... http://www.bulbs.com/espec.aspx?ID=11819&RefId=87For purpose of the project I need to power it with a small battery. One 9V battery would fit perfect, but would it burn the bulb out? Would it be better to try using two 3V coin batterys? Or would that even have enough juice to power the bulb? Thanks
- Matt (age 36)
Weaverville, NC
A:

Hi Matt,

That 6 Volt bulb sucks up 5 Watts of power at a current of 5/6 = 0.833 Amperes.  You can use a 9 Volt battery if you put a 1 Ohm resistor in series.   Unfortunately the battery won't last very long.   It's only good for about 0.4 Ampere-Hours,  maybe 20 minutes or so. 

You should consider using equivalent LED bulbs.  They are more expensive but use much less power for the equivalent light output. You would save money in the long run on batteries.

 

LeeH


(published on 12/22/2014)

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