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If I make a incandescent light bulb with a sturdy and thicker filament will it also increase the temperature or just make it more durable?

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    \$\begingroup\$ There are multiple things that have to be balanced in a lightbulb. The filament temperature cannot be too high or the filament will fail, and/or the color temperature will be higher than desired. So you may be able to tweak the filament a bit, but you probably cannot change it a lot without messing up something else. \$\endgroup\$ – mkeith Nov 27 '16 at 9:23
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In a tungsten bulb, the light output is related to both the surface area of the filament and its temperature. While the heat output is simply the input power minus the light power (which is usually in the range of 5% of the input power, can be 10% for halogens). Having a thicker filament will decrease the resistance which will cause more current to flow at the same voltage which results in more power and thus more heat, but a thicker filament at a constant power won't necessarily result in more heat, power out = power in.

Heat (watts) ~~= 0.95*input power (watts) for an incandescent globe.

Note: A tungsten heat globe will put out marginally more heat and marginally less light (I say marginally because even in the light globe, 95% of the power is heat anyway)

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A thicker filament (of the same material) will decrease resistance and therefore increase current flow, which in turn will increase power (P = IV) so yes, it'll make it hotter.

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  • \$\begingroup\$ Just thinking... a thicker filament will also have more surface to radiate from, and this would tend to make it cooler (in the sense that the equilibrium temp for a given current would be lower). Also we are implicitly assuming here that the filament is powered by a voltage source and current will adapt to the filament's resistance. \$\endgroup\$ – Sredni Vashtar Nov 27 '16 at 13:07

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