their primary property is light production, heat is a secondary feature
Hmm, not necessarily. Back in the days when this problem was originally offered incandescent bulbs were by far the most popular light source for facilities, and if you look at a graph[1] of such a bulb's output, you'll find the fast majority of it is below the threshold of visible light -- the real primary property of incandescent bulbs is IR (heat) production. As a physicist Feynman would be well aware of this, and hence I think he would approved of the low-tech intended solution over the suggested alternatives.
If you posit fluorescent lights, the traditional solution would still work. LED lights weren't stipulated as a special condition and even they are stated, they're not 100% efficient and hence might well work with the traditional solution.
Hmm, not necessarily. Back in the days when this problem was originally offered incandescent bulbs were by far the most popular light source for facilities, and if you look at a graph[1] of such a bulb's output, you'll find the fast majority of it is below the threshold of visible light -- the real primary property of incandescent bulbs is IR (heat) production. As a physicist Feynman would be well aware of this, and hence I think he would approved of the low-tech intended solution over the suggested alternatives.
If you posit fluorescent lights, the traditional solution would still work. LED lights weren't stipulated as a special condition and even they are stated, they're not 100% efficient and hence might well work with the traditional solution.
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