Re: luminous efficiency

[Larry Woolf <larry.woolf@GAT.COM>]

> -----Original Message-----
> From: Carl E. Mungan
> Sent: Tuesday, June 24, 2003 6:34 AM
> Subject: Re: luminous efficiency

> I agree that higher wattage means higher
> filament temperature, which tends to increase the light output in the
> visible by Wien's law.

The light output also increases because of the increasing filament diameter
and length (higher surface area for light emission) for larger wattage
bulbs:

25 W            0.0030 cm dia   56 cm length
75 W            0.0053 cm dia   55 cm length
100 W           0.0064 cm dia   58 cm length
200 W           0.0102 cm dia   72 cm length

Larry Woolf
General Atomics
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