Boing Boing editor/partner and tech culture journalist Xeni Jardin hosts and produces Boing Boing's in-flight TV channel on Virgin America airlines (#10 on the dial), and writes about living with breast cancer. Diagnosed in 2011. @xeni on Twitter. email: xeni@boingboing.net.

  • http://twitter.com/adam_kent Adam Kent

    You mean centripetal force – there’s no such thing as centrifugal force ( http://xkcd.com/123/ )

    • freds4hb

      Thank you!

    • http://doran.pacifist.net/ Doran

       Dang. You beat me to it!

    • echolocate chocolate

      It says literally in the comic you linked to ”Simply construct Newton’s Law in a rotating system and you will see a centrifugal force term appear as plain as day.”

      In many engineering and physics situations it is perfectly valid to use a centrifugal force to simplify the mathematics. Depending on your frame of reference it is just as “real” as centripetal force.

    • http://twitter.com/agrif Aaron Griffith

      If you believe Einstein, there’s no such thing as gravity either.

    • http://thisisonlya.blogspot.com robcat2075

       There is a “centrifugal force” if name something that.

    • Daniel Morgan

      Centrifugal: Center-fleeing
      Centripetal: Center-seeking

      Everyone here is correct. Saying there is no such thing as centrifugal force is a bit overly pedantic and smart-assed. I will say it in my classroom, but as a physics teacher, it is my job to be pedantic and after I believe that they understand that centrifugal forces are better described as tangential forces I will admit and acknowledge the meaning and usefulness of the term ‘centrifugal’. Centrifugal forces are technically tangential forces which when unchecked (unbalanced) by a centripetal force result in what we see here. Centrifugal force, even while better described by other forces, does mean something and communicate the situation.

      • http://www.facebook.com/craig.allen.90857 Craig Allen

        The best way to explain these two is what I was told way back when.  We were in the gym for a high school assembly of some sort.  I honestly don’t recall the whole situation, but I know it had to do with science.  In any case, the presenter pointed out that we were, individually and collectively, exerting a force (gravity) by sitting in the bleachers.  He then stated that the bleachers were exerting an opposite force upwards, which was why the whole pile didn’t collapse.  Then (the important part) he said that if we didn’t believe that, we should simply sit there for a couple hours and then notice how sore our butt was.  I think he made his point.  The Hamster Wheel works only because the Centripetal force offsets the Centrifugal force.  If it didn’t, the hamster would fly into orbit…or at least into the cage wall.

        • fjsr

          Unfortunately only half right. You do describe correctly the concept of normal force. Namely, that force which stops an object from, say, passing through another. The rotating disk exerts a normal force on the hamster. 
          Now, centripetal force is not really a type of force, but a generic term that describes whichever force  being used to keep an object in rotational motion, the normal force in this case, but the nickname can also be applied to the gravitational force that keeps the moon orbiting the earth. 
          Then, rather than saying that this force compensates a second, centrifugal force, we observe the acceleration provide by the force. This is Newton’s second law. The hamsters pressed against the wheel are constantly changing their velocity, by changing their direction of motion. The rate of change of the velocity is the acceleration which in this case is a vector that points towards the center of the wheel. 
          The centripetal force, a role played here by the normal force, provides the required acceleration.  

          But in then end, I think I should refuse to let physics get in the way of enjoying a good anecdote or punch-drunk hamsters. 

    • mtdna

      If Xeni had posted using the word centripetal I would have thought she was being a pedantic brat. Much like the person who corrected her.

      • Bruce Armstrong

        Please. Kent linked to an amusing comic and only “corrected” her in the same ironic spirit. The problem here isn’t pedantry, it’s reflexive literalism. Along with puerile name-calling.

        • SamSam

          Except the whole point of the comic is that it isn’t correct to correct people’s usage of “centrifugal force”… It seems to have gone over the heads of many people, but it’s the villain that Randall is showing as being correct in the comic.

  • K-9

    *harp glissando and wavy lines*  The Gravitron… the State Fair… the chili dog… the horror…

  • 10xor01

    Makes me wonder whether hamsters experience dizziness the same way humans do.

    • Just_Ok

      We could test for that, but we’d need a guinea pig.

    • mtdna

       My cat likes to sit on my office chair so one time I spun her really fast for a minute. She was so dizzy she fell over. It really surprised me. And made me feel bad. But I laughed anyway.

      • katkins

        She *meant* to do that!!

  • disconat

    As a physicist, my response to this video and the force debate is ” :3 ”

  • taj

    centrifugal? centripetal? whatever.

    I just know that I want to be reborn as a crazy hamster!   8-D

  • http://www.facebook.com/profile.php?id=100002490367699 P.s. Octochicken

    I think we’re all missing the main point here: hamster barf is the cutest barf EVAR.

  • pt68

    “Now where do you think you’re going?  Oh, me tooooooooooo . . . . . . .!!!!!! “

  • Gavin Smith

    “Centripetal force is an engineer’s phantom!” Aurther C. Clarke from Rama, it’s acceleration, not a force right? Isn’t that the real argument.

  • Rootboy

    I like the part where they went around in circle.

  • Henrix

    I think the main scientific point of this video is that Hamsters Just Want To Have Fun!

  • http://www.facebook.com/horan.shane Shane Horan

    See also http://www.youtube.com/watch?v=KDrpPqsXfVU

  • Justin Guild

    Things are squashed towards the outside in a centrifuge. If you say centrifugal force everyone will know what you are talking about.

  • huskerdont

    Science schmience. I like how the one hamster is getting forces exerted all over its ass and the other one just keeps on going.

  • ShawShaw

    Everyone’s getting pedantic about the physics terminology, yet NOBODY has pointed out that those are clearly gerbils and not hamsters?

  • xzzy

    I’m going to need to see this recorded at 1000 fps to be able to truly figure out what’s going on.

  • http://jeffsoesbe.livejournal.com yeff

    I swear I heard a bunch of tiny little cries of “WHEEEEE!”

    - yeff

  • http://walkingwithshimmer.wordpress.com/ Werther deGoethe

    Meth: not even once.

  • Velocirapt42

    Hamster running gleefully: Older brother. Hamster spun around relentlessly: Little sister. Trust me. 

  • DoctorDJ

    And those are mice, not hamsters!

  • http://www.facebook.com/profile.php?id=749173080 Robert McCoy

    Those are roborovski hamsters.  I have one.   Sleeps most of the day; runs six consecutive marathons (proportionate to his size) each night.

    • DoctorDJ

       Thanks. They don’t look like the fat-cheeked fur-balls I knew.

  • AnthonyC

    Centripetal force is the force applied by the bowl to the hamster along the direction of the radius of the bowl towards the center. It’s the force that keeps the hamster moving in a circle instead of bursting through the bowl’s wall. 

    If you write down the equations of motion in the hamster’s reference frame, then the coordinate change introduces a term called “centrifugal force,” which accounts for why the hamster feels pressed against the wall like you do in a gravitron. Physicists often call that a “fictitious force,” but it’s only “fictitious” if you think the laboratory reference frame has some special “reality” status. It doesn’t. 

  • NI MEN HAO-DY TRAMPOLINA

    Should not have watched this at school library. 

  • http://www.facebook.com/profile.php?id=1339830232 Gil Kirkpatrick

    … thus proving that hamster do not barf.