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Tom Mazanec
2004-Sep-05, 03:05 PM
If it could survive (bear with me on this) would a light bulb float in the Venusian Atmosphere? The vacumn is the best lifting agent you can have, after all, and the atmosphere is a lot denser.

cyswxman
2004-Sep-05, 03:19 PM
It might, given a surface density of about 65kg/m3 on Venus. I don't know what the density of a light bulb is, offhand. :-?

Squink
2004-Sep-05, 06:57 PM
I don't know what the density of a light bulb is, offhand. :-?I weighed a couple of 100 watt bulbs, and got an average weight of 35g. They displace about 150 ml water each, so their density is about 0.233g/cc.
The atmospheric density of 65kg/m^3 density at Venus' surface amounts to only 0.065g/cc, so a lightbulb would not float.

Glom
2004-Sep-05, 06:59 PM
I would think it would be crushed though. Besides, aren't light bulbs actually filled with argon?

TrAI
2004-Sep-05, 10:18 PM
I would think it would be crushed though. Besides, aren't light bulbs actually filled with argon?

I believe most incandescent bulbs use a nitrogen-argon mix at lower than 1 atmosphere pressure, though when it gets hot, the pressure increases to about 1 atm... But some bulbs use krypton instead of argon (krypton bulbs), or nitrogen-argon-halogen(halogen bulbs) mix, and some use just near vacuum. The basic idea is to prevent oxidation of the filament, reduce its vaporization and to reduce the heat transfer, so that the filament can get hotter...