4 ms·

I think the controversy is because that while being technically correct (bar a couple of mistakes) there are two main issues: 1) To get the result presented he

I think the controversy is because that while being technically correct (bar a couple of mistakes) there are two main issues: 1) To get the result presented heavily depends on the experimental setup and this appears to be hand-waved away (or for the cynics: deliberately obscured) as it would detract from the impact of the video. 2) The definition of "ON" in the video is not what anybody would reasonably define as "ON". This is not discussed in the video therefore potentially comes of as deceptive. As an electronic engineer I actually initially found the video confusing. I wasn't familiar with Veritasium before and I will admit my initial visceral reaction was "Oh he's just one of THOSE YouTube's and needs his clicks". It wasn't until I went back through to understand Veritasium's unspoken assumptions, simplifications and a couple of medium mistakes that I could say: yes this is technically correct. Personally I think with some better choice of wording the pitchforks wouldn't have come out as they have. Edit: Added word for clarity.

notfed 5y ago
I still don't buy "then yes this is correct". If "ON" is defined as a state where ANY electromagnetic field flows into the lightbulb, then it is "ON" even before you throw the switch, because other photons are already shooting around all over the place, including from the neurons in your body pondering the result just before you throw the switch. The definition of "ON" is exactly the main controversy with this and not a subtle detail.
- Ostrogodsky 5y ago
  Yes but that does not generate clicks,views and that sweet youtube money.Sorry but I cannot stand those kind of guys (he, Mark Robber and the likes). Khan academy is doing something 1000000 times more valuable.
- tsimionescu 5y ago
  Even if we also accept the unspoken assumption that there are no other photons/electrical fields outside the experiment, the experiment is still wrong, since the battery will produce a teeny tiny electrical field even if the switch is off. This is much more visible if we assume the switch is at one end of the light-second long cables - throwing the switch has little impact on the experiment as explained.
- kazinator 5y ago
  "ON" is when the filament of the bulb is hot enough to emit far infra-red rays.
BenFrantzDale 5y ago
His technical errors include the “correct” multiple-choice answer being that the time to turn on is “1/c s”. That evaluates to 3.3e-9 s^2/m. It’s not even a time. Failing basic dimensional analysis is grossly sloppy.
- Lerc 5y ago
  The correct units would have tipped his hand and led people to realize the 1m separation of the wires is relevant and thus people would reconsider antenna approaches. That would blunt the gotcha effect. That's not sloppy, it's disingenuous.
- shukantpal 5y ago
  It should be obvious that the "c" here was used as a magnitude not with units. Saying that's "failing dimensional analysis" is in itself grossly sloppy - since it totally misses the context.
  - SAI_Peregrinus 5y ago
    1m/cs is the correct value. Not 1/cs. The meters matters, hiding it makes it less obvious that the wire separation is what matters.
    - elsjaako 5y ago
      If you're going tot quibble about the units, it should be "1m/c". " 1m/c s" gives a result in s².
  - deleted 5y ago
    [deleted]
  - BenFrantzDale 5y ago
    But dimensioned quantities are meaningless without units. are you saying c has a value of 1.803e+12? Or that it has a value of 1? There’s a big difference between using furlongs per fortnight and speed of light as your units for speed. By saying “1/c s” rather than “1 m/c” he was just plain wrong and certainly in no position to be smug about it.

notfed 5y ago

I still don't buy "then yes this is correct". If "ON" is defined as a state where ANY electromagnetic field flows into the lightbulb, then it is "ON" even before you throw the switch, because other photons are already shooting around all over the place, including from the neurons in your body pondering the result just before you throw the switch. The definition of "ON" is exactly the main controversy with this and not a subtle detail.

Ostrogodsky 5y ago
Yes but that does not generate clicks,views and that sweet youtube money.Sorry but I cannot stand those kind of guys (he, Mark Robber and the likes). Khan academy is doing something 1000000 times more valuable.
tsimionescu 5y ago
Even if we also accept the unspoken assumption that there are no other photons/electrical fields outside the experiment, the experiment is still wrong, since the battery will produce a teeny tiny electrical field even if the switch is off. This is much more visible if we assume the switch is at one end of the light-second long cables - throwing the switch has little impact on the experiment as explained.
kazinator 5y ago
"ON" is when the filament of the bulb is hot enough to emit far infra-red rays.

BenFrantzDale 5y ago

His technical errors include the “correct” multiple-choice answer being that the time to turn on is “1/c s”. That evaluates to 3.3e-9 s^2/m. It’s not even a time. Failing basic dimensional analysis is grossly sloppy.

Lerc 5y ago
The correct units would have tipped his hand and led people to realize the 1m separation of the wires is relevant and thus people would reconsider antenna approaches. That would blunt the gotcha effect. That's not sloppy, it's disingenuous.
shukantpal 5y ago
It should be obvious that the "c" here was used as a magnitude not with units. Saying that's "failing dimensional analysis" is in itself grossly sloppy - since it totally misses the context.
- SAI_Peregrinus 5y ago
  1m/cs is the correct value. Not 1/cs. The meters matters, hiding it makes it less obvious that the wire separation is what matters.
  - elsjaako 5y ago
    If you're going tot quibble about the units, it should be "1m/c". " 1m/c s" gives a result in s².
- deleted 5y ago
  [deleted]
- BenFrantzDale 5y ago
  But dimensioned quantities are meaningless without units. are you saying c has a value of 1.803e+12? Or that it has a value of 1? There’s a big difference between using furlongs per fortnight and speed of light as your units for speed. By saying “1/c s” rather than “1 m/c” he was just plain wrong and certainly in no position to be smug about it.