2 ms·
Right, the wave filter effect caused by the thermal mass of the filament was my point. I'm not sure you've shown that this would be visible to a housefly as a
by SamBam 7y ago
Right, the wave filter effect caused by the thermal mass of the filament was my point.
I'm not sure you've shown that this would be visible to a housefly as a "slow pulse from light to dark," as the post I was replying to claimed. First of all, you said the power consumption will vary at a 60hz rate, but it seems to me it will vary at a 120hz rate, since the current will be at its max magnitude twice per cycle (as you say in the first paragraph). But more to the point, I don't know whether the temperature/lumens will decrease enough in 1/120th of a second to be visible to houseflies or anything else.
Trying to research the answer, I found this physics lab worksheet [1] from Pasco (the makers of sensors), for a high school lab measuring the output frequency of incandescent bulbs vs fluorescent bulbs, but without doing the lab I don't know the results.
1. http://phylab.yonsei.ac.kr/exp_ref/pasco/P54_BULB.pdf http://phylab.yonsei.ac.kr/exp_ref/pasco/P54_BULB.pdf
- Dylan16807 7y agohttps://www.quora.com/Would-a-120-volt-incandescent-bulb-operate-at-the-same-brightness-on-both-AC-and-DC-at-120-volts https://www.quora.com/Would-a-120-volt-incandescent-bulb-ope... The numbers here show a >25% difference for an example bulb. Also, even ignoring how the cooling starts off at its fastest, with radiation scaled to the fourth power of temperature... incandescent lights switch off in about a tenth of a second. Even if that was completely linear, it would be very visible. Even a 1% flicker would be visible.
- SamBam 7y agoHuh, good find. I wish the poster had some sources, especially for that initial temperature graph, but there's no reason to doubt it. Thanks for the research.