How Wrong Is VERITASIUM? A Lamp and Power Line Story

What people said

jacobolus · 2021-12 · Strong recommendation

Controversial is fine to the extent the controversy shows people struggling toward clearer understanding and better explanations, and as long as all parties are operating in good faith (i.e. not being deliberately misleading). Let me highly recommend Mehdi Sadaghdar’s (ElectroBOOM) excellent response video [VIDEO] which does a great job of empirically investigating and theoretically explaining the subtleties involved, in a polite, respectful, and entertaining way. I have similarly enjoyed the exchange between Sadaghdar and Steve Mould about the physics of the “chain fountain”. These kinds of friendly scientific “debates” show viewers (e.g. kids) a bit of how the scientific process and scientific discourse works, in a form that is more accessible and digestible than technical journal papers or history books. Having a discussion back and forth helps to improve both viewers’ specific knowledge and viewers’ processes for comprehending and interrogating new information, so long as the median viewer actually sees some of the responses. (Someone who only ever saw the first Veritasium video probably ends up with a somewhat wrong mental model.)

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afiori · 2021-12 · Recommendation

In my opinion the video made a couple of mistakes, which I think ElectroBoom's response* addresses nicely. Also its proof using the pointing vector to show the flow of energy is misleading; In the video Derek shows that the energy flows toward the lamp when the circuit is already in a stable configuration, but the point of the video is to explore what happens before the circuit reaches that configuration. This is relevant: assume that the right half of the cable is connected to the positive pole of the battery, in a stable configuration every point of the right half of the circuit has a positive charge (creating the poynting vector field as shown in the video) while 1/c seconds after the switch was closed the wire just to the right of the lightbulb will have a negative charge (the cable near it is positively charged from the battery and so the upper cable acts as a the negative half of a capacitor) which changes the direction of the poynting vector. In the end it felt like it was telling you that its message was that energy travels via the fields but what it actually said what that switches cause electric interference. * [VIDEO]

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naasking · 2021-12 · Recommendation

You should watch Electroboom's analysis if you want the full details from an electrical engineer: [VIDEO]

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