Air is mightier than eight Frenchmen

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19 Responses to “Air is mightier than eight Frenchmen”

  1. Of course, the ball is always the winner, but the rig for applying human force against the vacuum looks horribly inefficient.  There’s a lot of human energy pitted against itself instead of against the ball.  Look at the way those wood bars wobble!  Any physicist out there to clarify this in a professional manner?  I’m just a sailor.

    • jandrese says:

      It looks to me like almost all of the force gets applied to the ball, although some energy is lost in waggling the ropes around like that, I think most of it is going into the ball. 

      What that rig does is prevent spikes in the load however.  If one team were to make a sudden jerk it would tend to pull on the other team and smooth out the force on the ball.  This is important because even a tiny momentary crack would let air in and weaken the seal.  If the ball were anchored to a wall and the people on the ropes were running away to give it the hardest jerk possible…they would probably still fail but maybe not. 

  2. jncc says:

    Those poor children – don’t they have x-box in France?

  3. timmaguire says:

    The part that always amazed me most is that they had pumps and seals capable of creating a vacuum in 1654.

  4. jandrese says:

    It didn’t have to be a perfect vacuum.  Just so long as you got an appreciable amount of the air out of there long enough for the demonstration you were fine.  Wetted leather would have worked to seal the ball (especially with the air pressure clamping down on it), and the pump would have been feasible if inefficient I think.  

  5. Roy Trumbull says:

    The pressure is 14.7 lb per square inch. Another demonstration is to lay a sheet of newspaper on a table covering about half of one of those cheap yardsticks you find in some stores for measuring things. A rapid whack downward on the exposed end will break the yardstick. Same principle.

  6. Preston Sturges says:

    The other gee-whiz crowd pleasing experiment of that era was to fill a sphere (like a cannonball) with water and then put it  out in the square some place like Moscow until the wter froze and it exploded or blew out the screws used to plug them.

  7. SedanChair says:

    I propose that the next probe we send into space contain only 2 videos. 

    The one above, and this one:
    http://www.youtube.com/watch?v=c8Pfdoknn6Q 

    Let the extraterrestrials draw their own conclusions.

    • Tom Tjarks says:

       Opening ceremony for a tournament?  If I remember correctly the white belted sumo is a high ranking champ, and the two on each side of him are a step below (or junior) sumo… beyond that, I’m totally guessing.

    • bcsizemo says:

      No, just no.  Aliens will think that we all communicate in clicks, beeps, and shutter sounds.

      -Don’t people know digital cameras have sound controls?

    • Ipo says:

       Are you sure that is not an alien video we received from outer space? 

  8. Roose_Bolton says:

    Air is technically 2 Frenchmen. So this is a story about 2 Frenchmen beating 8 Frenchmen.

  9. wrwetzel says:

    Guessing the diameter to be about 18″, the force holding the hemispheres together is 3740 pounds. That’s a lot of horizontal pull. If I’m off a bit and it is 24″ then the force is 6650 pounds. 

  10. Andrea says:

    In Magdeburg, you can buy chocolates shaped like the Magdeburg Hemispheres.

    (I love practical physics demonstrations.)

  11. BombBlastLightingWaltz says:

    All non-believers where drawn and quartered, 1654!

  12. GertaLives says:

    Really, no French weakling jokes? Am I on the wrong internet?

  13. niktemadur says:

    Oh damn, the original spectacular physics experiment!  Who was the guy, Maggie?  Without Googling it, my money’s on Leeuwenhoek.

  14. Amelia_G says:

    Magdeburg has put up half-sphere statues around town that people have decorated.

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