I’d expect grade schoolers to understand how to do it but that’s just me.
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Well, yeah. Basic electronics skills and knowledge are life skills I think everybody should possess but I can’t assume everybody has - even those ostensibly smart people that graduate from a fancy engineering school with an unrelated degree.
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This is a common trick question that is meant for children that is used regularly to “prove” that college educated people “don’t understand the real world.” I had hoped this was an exercise in showing how to use electronics to light a 120W bulb with a 1.5V battery.
A lot of those appear to be household candelabra bulbs that are likely 40-60W bulbs from a hardware store (they even have frosted glass to look better if the bulb is seen) so they could get the shot of people not knowing what to do even if they did. The small bulb appears to be a 5Wish bulb used in old-timey signs before LEDs, and the one used to show the trick to children.
If someone came to me and asked “can you light a bulb with a battery and a wire?” I would say “depends” because there are literally millions upon millions of possible components that can be used for a bulb, wire, and battery. I know plenty of eggheads that would take time to answer because for some reason vague questions are their anathema.
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I think this is the overall point of this segment but it has been broken out in a way to make students look “stupid.”
ETA: It doesn’t help that the trial is designed in such a way that it’s difficult to complete the task from a dexterity standpoint.
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I rewatched and I don’t know what the fuck this bulb is…
In real time it looked like it had threads, but it doesn’t have the pins of a bayonet connection either. I don’t know where they found this thing.
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Looks like something like this:
I know what a bayonet bulb looks like, but the bulb used isn’t a typical bayonet bulb either. It’s probably for maritime use or something else that uses funky sockets.
Me too. I was initially thinking that a transformer would be made from the wire (like I made in a GCSE physics lesson), but that wouldn’t get around W=VA.
I’ll admit that I haven’t actually watched the video yet
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Lighting a 120W light from a 1.5V source wouldn’t be hard. I mean you’d need 80 amps of current, but as long as the light bulb only had a resistance of 0.01875 ohms it’d work briefly. I’d recommend a D cell or larger battery.
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The only problem is that the “other” type of student is hard to test for. I was very hands on and could look at most circuits and at least have a decent understanding of what it was doing. I understood the theory well but the application of the mathematics was always my weak point. Of course software does a lot of that for you today, but that doesn’t help on finals.
My circuits III professor designed all his exams and final to be done without a calculator. All math was at a fifth grade level or so and I did well in his class. It was fun watching people breakdown because they didn’t understand how an NP junction formed a capacitor. Needless to say most of my classes were not like that.
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That’s twice as much current as a defibrillator uses at its very peak.
Roughly equivalent to the resistance of two inches of 30-gauge wire. A lightbulb has a teensy bit more load than that.
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So I’ve finally taken the time to watch TFV and I have no idea what I just watched.
Even if you could wind enough wire (around what?) to make an air-core transformer, you’d still have the problem that the battery only puts out DC.
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Not just the bulb, but the battery as well would need extremely small equivalent resistance. bcsizemo was just kidding.
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“Poorly edited video”? Or edited to prove some point tangential to “lighting a bulb”? They probably asked lots of grads, and discarded videos that didn’t show what they wanted.
The one guy who hesitates for a long time before saying “yeah” seems to be looking at the question for some kind of trick, because it’s both too simple, and very broad, with lots of variables (like if the bulb is actually working, if it’s properly rated to the battery, etc.)
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Yeah, engineering profs tend to enjoy making things more difficult than necessary. You also, of course, have weed out courses. Anyway, I’m glad you said that about the exams designed to be done without a calculator. I’m hoping to begin my PhD studies soon, with the intent of becoming a university professor. I think that sounds like a good idea. I’m sure they will try to beat it out of me, but I will try to resist.
The conditions under which hoi polloi get to the Ivy League are a bit different from those under which people like the Bushes get there. It’s something to do with $$ signs.
(But I agree in any case. The important thing is to go somewhere that best suits your needs. I went to Cambridge, and it was a mistake. Now, I would never advise anyone to go to a university based on prestige.)
Your professor was a good teacher.
I am currently helping a physics student. He is extremely fast on the maths, but he lacks a lot of the kind of background you describe. Recognising the meaning of questions and the approach to follow is hard if you can do all the equations but don’t, for instance, immediately grasp what happens when a current flows in a wire.
Also, see Feynman’s account of his experiences in Brazil (the physics education, not the samba and the extremely nice young women.)
I think you had it right before watching. The point of the segment before it got extracted and re-titled was not that Harvard or MIT graduates are too stupid to hookup a lightbulb, but that teachers have to be careful about making assumptions on what is logical and or common knowledge. Just because someone is smart and well educated doesn’t mean that they know what you think they should know.
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Whether or not that is what was intended, that’s a great message to take from it.
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