FULL Solution to the Pole Barn Paradox (in 7 minutes)

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  • Опубликовано: 21 дек 2024

Комментарии • 39

  • @zhelyo_physics
    @zhelyo_physics  2 года назад

    If anyone is wondering where the length contraction formula comes from, check out my derivation:
    ruclips.net/video/tZfZujwCi28/видео.html

  • @Mysoi123
    @Mysoi123 2 года назад +4

    The Lorentz transformation has changed how I see the world!
    it is pretty mind-blowing that the notion of time and space are observer-dependent!
    Love your explanation!

    • @zhelyo_physics
      @zhelyo_physics  2 года назад +1

      thanks a lot for your comment! I agree 100%, I think I need to do a separate video on that very topic.

    • @Mysoi123
      @Mysoi123 2 года назад

      @@zhelyo_physics excellent!

  • @zhelyo_physics
    @zhelyo_physics  2 года назад +8

    I remember struggling with this in my first year university relativity class, still one of my favourite subjects! : )

  • @thomasadams1011
    @thomasadams1011 2 года назад +1

    Loved the video! Would you be able to recommend some of your favourite resources for SR and the pseudo paradoxes?

    • @zhelyo_physics
      @zhelyo_physics  2 года назад

      thanks a lot! I'll see if I can do a video on that, interesting question! I use a variety of textbooks normally, but these days there are so much things available online for free too.

  • @muizbajwa
    @muizbajwa 2 года назад +3

    damn my guy! love your style and energy🥵

  • @Abc-vc4ml
    @Abc-vc4ml 2 года назад +2

    Hey, I’ve just started year 13 and want to learn Special Relativity in my own time. Any resource recommendations for doing this? I’m thinking of using Leonard susskind’s theoretical minimum book/lectures.

    • @zhelyo_physics
      @zhelyo_physics  2 года назад +2

      Excellent! Leonard Susskind's lectures are some of the best, he is a world class physicist and one of the best people to learn physics from.
      Check out also: www.feynmanlectures.caltech.edu/ Volume 1 has pretty much complete special relativity lecture notes. Ideally you want to practice on some special relativity problems though, I normally use Young and Friedmann University Physics but I am sure there are many options out there. Good luck!
      I have a consise intro to special relativity here which I did some time ago too: ruclips.net/video/3HhuAa5YnuQ/видео.html

  • @marcoaltamura7512
    @marcoaltamura7512 2 года назад +1

    Crazy! Now I'm asking myself: what would an observer at rest see (he probably wouldn't even be able to tell something happened at those velocities, but, theoretically, would the closing of the doors be synchronous or not to him?)
    I'm supposing that this observer is in the frame of reference of the barn, given they have the same speed, so we could use a similar analysis to find out about the time delay between the openings of the two doors. Am I right?

    • @zhelyo_physics
      @zhelyo_physics  2 года назад +2

      So technically, the frame of reference of the barn would be the same as the frame reference of an observer on the ground that is stationary (with respect to the barn).
      And yes you are right : ) They would see (well probably record, hard to see stuff moving at nearly the speed of light I imagine) the pole length contract along its direction of motion.

  • @sylar1923
    @sylar1923 2 года назад +1

    Hello sir i want to study computer science for university, how useful is physics for CS and in which way? Thank you very much

    • @zhelyo_physics
      @zhelyo_physics  2 года назад +1

      It is a similar way of thinking/problem solving: ) very useful when dealing with arrays/vectors and crucial ir you are ever building game engines I imagine

  • @norbertomarquez-arroyo477
    @norbertomarquez-arroyo477 8 месяцев назад

    If the doors were attached to electrical switches and the those electrical switches were attached at the input of an AND gate such that when both doors close the output of the AND gets set to a high voltage to trigger the detonation of an explosive that blows up the barn. How do we resolve both perspectives of the runner and the farmer? The runner will see that he will not trigger the explosive because the pole won’t allow both doors to close and yet the farmers perspective sees both doors close that cause a detonation. Is the runner both alive and toast?

    • @zhelyo_physics
      @zhelyo_physics  8 месяцев назад

      very interesting question. Nope, the situation is mathematically exactly the same as the one described in the video. The signal will travel at the speed of light leading to the same resolution as described mathematically at the end. Hope this helps!

  • @H1289-h8o
    @H1289-h8o 2 года назад

    What books would you recommend that has really good physics problem solving problems? I am looking to apply to Oxford for engineering so I want to improve my skills

    • @zhelyo_physics
      @zhelyo_physics  2 года назад

      my recommendation: ruclips.net/video/UbCb_-GtX4E/видео.html I would also have a browse on the Oxford Oxnet Programme and also - Isaac Physics has some AMAZING problems : )

  • @nimrodnadborny4081
    @nimrodnadborny4081 2 года назад

    Wow, so interesting.
    I’m starting my degree this year in math and physics double major and I’m taking introduction to modern physics in the summer, so exited

    • @zhelyo_physics
      @zhelyo_physics  2 года назад

      Fantastic! You will enjoy it for sure! Actually, this is the exact double major I did at university :D

  • @abdurrahman2008
    @abdurrahman2008 2 года назад +2

    I love Ur videos. Physics is really good.

    • @zhelyo_physics
      @zhelyo_physics  2 года назад +1

      Thanks a lot! Much appreciated and thanks for your comment!

  • @VortekStarling
    @VortekStarling 2 года назад

    Can you solve this problem? To explain how 2 laser beams going in opposite directions from the middle of a moving train car to clocks at each end could appear to be moving at the same constant speed in both directions to an observer on the ground, Einstein suggested that the clock at the rear would show a time ahead of the time on the front clock from the observer's perspective, although they would both be moving at the same rate due to moving at the same relative speed. Both clocks would be behind the observer's clock, due to time dilation, but the front clock would be behind it by more than the rear clock, in Einstein's mind.
    The question is how did the two clocks come to vary from the observer's clock by different amounts in the first place. Einstein never explained that, because he couldn't. It's the same Lorentz Transformation factor for the entire train car and the entire car accelerated at the same time and rate so how did the two clocks come to vary by different amounts simply by being at different ends of the train car? You can't answer it because nobody can, because Einstein's theory is clearly flawed.

    • @zhelyo_physics
      @zhelyo_physics  2 года назад

      Actually, I don't see a problem with that. The Lorentz Transformation is applied to an event rather than a system,frame of reference. The problem described above is pretty similar to the pole paradox and information transfer (opening the gates could only be done by sending a signal in the direction of travel and opposite the direction of travel). Einstein's theory is very very well tested in experiment. I wouldn't be surprised if similar maths is used in GPS triangulation with satellites or something similar.

    • @VortekStarling
      @VortekStarling 2 года назад

      @@zhelyo_physics The Lorentz Transformation equation only gives one time dilation factor for an entire moving frame. That means that all clocks in that moving frame would be equally behind a clock in a stationary frame from the stationary frame's perspective, meaning they should all show the same time which is equally behind the stationary frame's time. Yet to account for the rearward beam hitting the rear clock before the forward beam hits the front clock, from the stationary observer's perspective, the time seen on the rear clock would have to be ahead of the time seen on the front clock the whole time, even before and after the beams were shot, because shooting the beams wouldn't make the rear clock suddenly jump ahead of the front clock from the stationary perspective. So how did they get to be in that state, showing different times from the stationary perspective instead of the same times like they logically should?

  • @Pavan_Gaonkar_abc
    @Pavan_Gaonkar_abc 2 года назад +1

    Theses type of problems/ideas makes physics much more interesting 😍

    • @zhelyo_physics
      @zhelyo_physics  2 года назад +1

      I agree, all the relativity thought experiments are great!

  • @blueofficial785
    @blueofficial785 2 года назад +2

    Relativity is sometimes confusing but this was an amazing video, love the enthusiasm

  • @Dan-pi6dx
    @Dan-pi6dx 2 года назад +2

    beuj i didnt even know stuff contracts at that speed

    • @zhelyo_physics
      @zhelyo_physics  2 года назад +1

      technically it happens at lower speeds too, but the difference is small enough to not be noticed/measured.

  • @Abrar69
    @Abrar69 2 года назад +2

    I've already encountered this problem. This was really exceptional and fun. Great explanation anyway!

    • @zhelyo_physics
      @zhelyo_physics  2 года назад

      Thank you so much for your comment, this is much appreciated!

  • @alexandre_18771
    @alexandre_18771 Месяц назад

    Imagine that there is a device cleverly assembled such that when both doors are closed, it triggers a digital circuit, that will activate a bomb. Will the bomb explode or not? It seems like in one case yes and in the other no.

  • @JungleJargon
    @JungleJargon 2 года назад

    There's no paradox, both contract.

    • @zhelyo_physics
      @zhelyo_physics  2 года назад +1

      Well virtually in all cases of relativity paradoxes there are only apparent paradoxes. The paradox is resolved though not by contraction in this case but by the simultaneous events not being simultaneous in the other frame of reference.

    • @JungleJargon
      @JungleJargon 2 года назад

      @@zhelyo_physics Yep! 👍

  • @qualquan
    @qualquan 8 месяцев назад

    Yes he is using FOS but very poor exposition