How would steam pressure move a lid?

Discussion in 'Physics & Math' started by Bob-a-builder, Jun 14, 2019.

  1. Bob-a-builder Registered Senior Member

    Messages:
    123
    Would YOU care to make an attempt at actually answering? Maybe it's over your head also.

    I mean yours was the 60th comment. Perhaps it is not a simple physics answer you can resolve?

    The child level experiment is as follows.

    1) You get a meatloaf container.
    2) You get a flat 6 oz piece of sheetmetal with a 10% overlap (for meatloaf container as you will say "overlap of what?" otherwise).
    3) You fill the pot with water and boil.
    4) You put the lid on.

    If you do not know the answer simply ridicule the experiment. Not everyone is capable of child level physics.

    I remember you from your pushing of woo on the computer thread. If you cannot answer it. Just say so.

    At this point I am willing to go buy a meatloaf pot (not my thing) and film this if only to educate many here.

    The lid will NOT stay on the pot. The lid WILL expose a corner first. You can figure out why all by yourselves.

    This is supposed to be a science forum, and from what I have witnessed nobody seems to actually know any science.

    This is PHYSICS. Child level physics. This is not woo. Pots and lids do exist.

    (I predict the next comment will be Dwyddry quoting this entire message and disagreeing with every line - How the heck can you disagree with a bloody question?... I don't know.. but he will).
     
    Last edited: Jun 17, 2019
  2. Google AdSense Guest Advertisement



    to hide all adverts.
  3. billvon Valued Senior Member

    Messages:
    21,644
    Or . . . keep digging. Completely up to you.
     
  4. Google AdSense Guest Advertisement



    to hide all adverts.
  5. James R Just this guy, you know? Staff Member

    Messages:
    39,421
    Sounds like a great idea. It's never a bad idea to do the actual experiment!*

    Please go right ahead and assume there's nobody here intelligent enough to work out the answer without you doing the experiment. Post the video after you've done it.

    You never know. One or more of us might just learn something.

    ---
    * Well, it depends on what you're experimenting with, I suppose, but in this case it sounds harmless enough.
     
    Last edited: Jun 17, 2019
  6. Google AdSense Guest Advertisement



    to hide all adverts.
  7. Bob-a-builder Registered Senior Member

    Messages:
    123

    Yes. They need an education. Agreed. I just wish one person would pose their view of what might occur before I did such, but nobody is willing to suggest what would occur if


    The child level experiment is as follows.

    1) You get a meatloaf container.
    2) You get a flat 6 oz piece of sheet-metal with a 10% overlap (for meatloaf container as you will say "overlap of what?" otherwise).
    3) You fill the pot with water and boil.
    4) You put the lid on.

    Even you did not hazard a "guess" at what might occur. I would be more fun if someone will just say the lid will not move first so I can prove them wrong.
     
  8. RainbowSingularity Valued Senior Member

    Messages:
    7,447
    please explain how sheet metal is equal to 5 ton granite box ?

    that bit i get lost on.

    did they uncover the electric cords from the 5 ton granite boxes to an electrical grid used for heating ?
     
  9. Michael 345 New year. PRESENT is 72 years oldl Valued Senior Member

    Messages:
    13,077
    They found a skeleton with fingers stuck in the wall

    Early electrician apprentice changing a fuse by hand while the sarcophagus was still live

    Please Register or Log in to view the hidden image!

     
  10. cluelusshusbund + Public Dilemma + Valued Senior Member

    Messages:
    7,999
    Ok... heres what i suspect will hapen:::

    Steam will begin to escape at an irregularity in the lid/pot which is least effective at sealin it in... an if the escapin steam is strong enuff... the lid woud be pushed up at that irregularity... an ether drop back down an do this over an over... or continue to stay pushed up if the strength of the steam increases enuff an is steady... but ether way... the lid is likely to shift until thers a gap in lid an pot thats big enuff for the steam to escape wit-out liftin the lid.!!!
     
    sideshowbob and sculptor like this.
  11. Bob-a-builder Registered Senior Member

    Messages:
    123
    Thank you for saying what I've been suggesting the entire time. I feel a corner would be the most likely final escape of pressure, but if the lid is moving thats just easy math.

    Thanks for actually answering in post 67. Appreciated. You saved me from buying a meatloaf container and filming this.
     
  12. cluelusshusbund + Public Dilemma + Valued Senior Member

    Messages:
    7,999
    One corner coud not lift alone... ether two corners woud lift at the same time or 3 corners woud lift at the same time... an two corners woud take less pressure to lift.!!!
     
  13. Bob-a-builder Registered Senior Member

    Messages:
    123
    No... I'm not suggesting that. That's impossible. When the cover skews as moving on air pressure. The lid would either fall off or expose an area large enough to release maximum pressure. I am not suggesting and never have and never will suggest that just 1 corner would lift. That's insane.

    The test is how the lid would travel and "land" (stop floating). I suggest the lid will either fall off completely or expose a gap large enough to emit the necessary pressure , so it can again fall in to rest with gravity. I suggest such a gap would be in the corner. The gap. The space where gas is released.

    The gas could never release if the corner of the lid was even near the corner of the meatloaf container.

    I am saying that in most cases. A corner would be exposed by the sliding lid before a length or width.
     
  14. cluelusshusbund + Public Dilemma + Valued Senior Member

    Messages:
    7,999
    Ok... got it

    Please Register or Log in to view the hidden image!



    The lid woud shift an expose a open corner of the pan allowin the steam to escape... you prolly right.!!!
     
    Last edited: Jun 17, 2019
    Bob-a-builder likes this.
  15. Neddy Bate Valued Senior Member

    Messages:
    2,548
    I don't see any reason to think the steam would have to move the lid horizontally (and expose a corner of the pan) in order for the steam to escape at an optimal rate. The steam could just as easily move part of the lid upward to vent the steam.

    The lid would then simply oscillate up and down, venting the steam whenever the pressure gets high enough to lift the lid a little bit. Given a long enough period of time, the somewhat random movement of the lid may eventually cause it to move horizontally, but it would not be necessary, nor expected in the short term.
     
    sideshowbob likes this.
  16. cluelusshusbund + Public Dilemma + Valued Senior Member

    Messages:
    7,999
    The steam will begin to realease at the pont of least resistance... an that pont will most likely be to the right or to left of the center of the lid... an that woud tend to push the lid to one side or the other... which over time woud most likely cause a corner to open up than a complete side.!!!
     
  17. Neddy Bate Valued Senior Member

    Messages:
    2,548
    That is like saying that if you raise your right arm, it would force you to walk toward the right.
     
  18. cluelusshusbund + Public Dilemma + Valued Senior Member

    Messages:
    7,999
    If the lid fits good enuff an the pressure is strong enuff the lid will raise upward of course... an the release of steam will begin at a pont of least resistance... an if the lid does move ether strait back or to one side or the other over time... i thank that movement may apear to be random... but even so ther will be causes for its movements... an i gave reasons why i thank it will most likely move ether left or right (which woud expose a corner) insted of just movin strait back.
     
    Last edited: Jun 18, 2019
  19. Neddy Bate Valued Senior Member

    Messages:
    2,548
    The reason I think its movements would be fairly random are because the OP went to great lengths to assume the pan and the lid were perfectly flat. So it would be just as likely for steam to escape at the North side as it would be for the steam to escape at the South, East or West sides. If the lid oscillates up and down with openings temporarily forming on various sides, the lid would not be meandering in any particular direction horizontally.

    But even a random movement could eventually expose a corner or two, if given enough time. The OP also stated that the lid only overlaps the square pot by about 1 inch on all sides, so the lid would only have to move about 1 inch or so to expose a corner or two.
     
  20. cluelusshusbund + Public Dilemma + Valued Senior Member

    Messages:
    7,999
    So if conditions was all perfect... the complete lid woud just hover in place... or if the pressure decreased the lid woud fall back into its original position.!!!

    That does simplify thangs.!!!
     
  21. cluelusshusbund + Public Dilemma + Valued Senior Member

    Messages:
    7,999
    Yes if conditions are not perfect an ther are irregularities an the lid does change positions... i thank it most likely for a corner to be exposed rather than a complete side.!!!
     
  22. Neddy Bate Valued Senior Member

    Messages:
    2,548
    Even if all conditions were perfect, I don't think the lid can hover in place, because I don't think there would be enough steam flowing out to do that. I think it would have to tilt in random directions while venting from random locations.

    A complete side becoming exposed is just the same thing as two corners becoming exposed at exactly the same time. Even if that were to happen, one could argue that one corner was exposed before the other, by some arbitrarily small amount of time. So, yeah, I think we agree!
     
  23. cluelusshusbund + Public Dilemma + Valued Senior Member

    Messages:
    7,999
    I thank that creatin enuff pressure from rapidly boilin water woud be the least of the prollems tryin to get the lid to hover (at low altitude… lol)... but no… just a flat lid on a regular pan ant gonna hover in place.!!!

    It woud be fun to experiment wit a square pan an a flat 1 inch oversized lid.!!!

    I have a 9 inch square metal pan... that i coud grind the top a bit wit a 12 inch sandin disc to help insure a perty even/flat surface… but i dont thank i have anythang to use for the flat lid :-(
     

Share This Page