Yeah, no. I actually paused the video at that point and said "what the hell?? that was 12 degrees (as someone in the crew predicted), not 16-17 degrees!". It wa

Yeah, no. I actually paused the video at that point and said "what the hell?? that was 12 degrees (as someone in the crew predicted), not 16-17 degrees!". It wasn't even 15 degrees, which was clearly when the object actually started sliding in the first experiment. I wanted to continue watching the video because I should watch the whole thing if I'm gonna criticise it. But then he lied about the stapler. Just because he skipped counting "15, 16, 18, 19.." doesn't mean it didn't start sliding at 17 degrees, which is in fact within one degree of the unweighted yellow box (if you take his word for it, or within two degrees if you go by what you saw), either way definitely closer than when the weighted yellow box started sliding. If there's one thing this video tells me it's that the angles that he measures are accurate to no more than +/- 5 degrees. Therefore drawing conclusions about differences that are less than that is FLAWED. What he is demonstrating is how NOT to do a physics experiment. It's terrible! If he just wanted the audience to take away from this video that friction is independent of weight or whatever, it would have been better if he had just told the story in front of a blackboard or something. I stopped watching when he claimed the two cylinders of different length made "no difference". https://i.imgur.com/SXg4FRk.png https://i.imgur.com/SXg4FRk.png FFS this is just embarassing. It's pretty obvious that this guy is just going through the motions telling a rehearsed story that has not much to do with the actual outcomes of the "experiment" he is trying to make us believe he is performing. If you think that's okay, then imagine replacing this "demonstration" with an animated cartoon of the very same. How convincing would that be to you? Because he does say "you just gotta take my word for it", a lot. > this isn’t a formal proof or a research paper seeking peer review No but it is a youtube video of a physics experiment. They don't get peer reviewed. What is it exactly that you are trying to say? Am I not allowed to expect some amount of rigour and honesty unless it's a research paper seeking peer review? If it intends to be educational, at least don't show that apparently it's okay to fudge results in a physics experiment as long as you're a MIT professor and say "just take my word for it". Because that's my takeaway from this video: "this guy probably shouldn't do physics experiments". Because most Youtube videos on scientific topics I've seen, they either perform the experiment correctly, but if they don't get the results that they "should", they own up to it. Sometimes they record the experiment again, and they TELL you it failed at first and what they changed. Sometimes I even hear them lament that they filmed a great experiment, got the results they wanted, but had to trash the video because it just looked fake and unconvincing (because of the angle, timing, just didn't work on camera, etc)[0]. It sucks for their time and effort but they know they can't use it because it would completely undermine their point when the comments point out how fake it looks. Guess who disabled commenting on their video? You're absolutely right about not seeking peer review, or in fact any review. Quick check of some other vids on that Physics World youtube-channel, in particular a few videos with a professor or PHD talking or doing an experiment: NONE (of the ones I clicked so far) had their comments disabled! So what I'm guessing happened here is, a LOT of people had issues with the fudging of the experimental results and dis-ingenuity of what they supposedly demonstrate. They commented and pointed out that what the man says is happening isn't actually what they see is happening, and that makes it really hard to "just take his word for it". I doubt it even got really ugly before someone's ego got a dent in it and instead of deleting the crummy video, they took the much easier road of deleting the criticism. If he's doing this all the time in Skype demonstrations all over the world, why put up a video where the first couple of experiments clearly don't show what he's saying they show? [0] That example btw, was Tom Scott a couple of times, huge respect. Not only owning up to failed experiments, but clearly talking about the experiments he DID do, that DID NOT work out as he hoped, so much that he didn't want to publish them (on YouTube), but he still said he did the experiment. That's a HIGHER STANDARD actually than a proper scientific formal proof or peer-reviewed research paper is held to!!!! Peer review doesn't check for publication bias.