Re: Season misconceptions in newspaper

[Bernard Cleyet <anngeorg@PACBELL.NET>]

What units did the tags use?

Are you certain it was lamp cost saving and not electricity?

there are two competing factors in incandescent lamps, life and luminous
efficiency.  Halogen cycle lamps may be operated at the temperature of
std. gas filled lamps, and, thereby, have a considerably longer life.
From an old table (< '68 ca.) two comparable lamps:

Both std. and Iodine cycle  (quartzline) 500 W operated at a color Temp.
of 3200.  They both emit ~ 10K Lumens; the iodine has a life of  2,000
hr..,  the std (CZX projection) only 25 hr..

more info.  including a reflection coating that much increases the
efficiency:

http://www.lampcenter.com/halog_2en.htm

bc whose home is almost completely fluorescently lighted




John Clement wrote:

> That may be true, but the tag actually implied you were saving
> electricity.  It did not have any information about lifetime or bulb
> cost.  It looked so impressive until you read the actual information.
>
> What surprised me is that 60W halogen bulbs have comparable rated light
> output to 60W regular bulbs the last time I looked at them in the store.
> They usually have some claims about being "more efficient".  Perhaps
> they put out more light in the more visible portion of the spectrum to
> validate the claim of higher efficiency?
>
> Things have not changed since they sold in radio ads genuine 14 carat
> simulated gold rings.
>
> John M. Clement
> Houston, TX
>
>
>
> > -----Original Message-----
> > From: Forum for Physics Educators [mailto:PHYS-L@lists.nau.edu] On
> Behalf
>
>
> > Of Tim Folkerts
> > Sent: Saturday, June 21, 2003 3:32 PM
> > To: PHYS-L@lists.nau.edu
> > Subject: Re: Season misconceptions in newspaper
> >
> >
> >
> > > I have an interesting tag that I stole from a lamp in a store.  It
> > > claims that an expensive lamp which uses a 60 W halogen bulb is more
> > > efficient and saves money over a conventional 60 W bulb.  I compared
> the
>
>
> > > rated lumens and wattage with a conventional light bulb and found
> they
>
>
> > > were comparable.  Hmmm  I have asked students whether the claim was
> > > true.
> > Of course, if the halogen bulb costs 3x as much, but lasts 10x longer,
> > then
> > it DOES save money!
> >
> >
> > Timothy Folkerts
> >
> >
> > "The only thing necessary for the triumph of evil is for good men to
> do
>
>
> > nothing." - Edmund Burke