The coin on lemon trick

redvee
redvee Posts: 11,922
edited October 2011 in Commuting chat
No doubt a few of us have seen the jug of water at the bar of a pub with a lemon floating in it with the challenge of balancing a coin on the lemon for 5 seconds. Is it possible? I'm thinking not cause of the centre of gravity changing when the coin is on the lemon. My local JDW have got it on their bar with a 50% discount as the reward.
I've added a signature to prove it is still possible.

Comments

  • whyamihere
    whyamihere Posts: 7,716
    Is there a rule against introducing a little bit of liquid nitrogen?
  • It's an old gravity experiment - I remember doing it at school!

    The answer is that it's not possible, the only way to do it would be to cut a slit in the lemon and push a larger/heavier coin, such as a 50p, into the bottom, lengthways along the lemon, and then balance a smaller coin on top.

    As you say, putting a coin on top moves the lemon's center of gravity to its top, which means it'll roll round. If you can put something heavy enough in the bottom, it won't move the CofG.

    Simples! But I doubt the pub will let you do that...
  • If the centre of buoyancy is above the centre of gravity the lemon will remain stable.

    Adding the coin moves the centre of gravity above the centre of buoyancy ant the the lemon flips over. The CofG of the lemon is probably near its centre of buoyancy.

    I presume you have to use a regular coin and not one made out of something very light weight.

    Its e-lemon-tary physics.

    (sorry)
    Racing is rubbish you can\'t relax and enjoy it- because some bugger is always trying to get past.
  • Headhuunter
    Headhuunter Posts: 6,494
    Health and safety alert... Isn't that water for human consumption? And you want to start putting coins, possibly the dirtiest things on the planet, into it?! Eurgh....

    Just like when I ordered a falafel kebab thing at Bestival recently, the woman made it carefully with her hands clad in rubber glove things, but then promptly proceeded to take my cash without removing the rubber gloves. Some people are utterly clueless! Is this not just common sense? Does she think that rubber is somehow impervious to bacteria?
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  • mudcow007
    mudcow007 Posts: 3,861
    ive seen this at loads of festivals, generally its 50p a go an the winner takes all the 50ps at the bottom of the jug

    never seen anyone win it though
    Keeping it classy since '83
  • desweller
    desweller Posts: 5,175
    Health and safety alert... Isn't that water for human consumption? And you want to start putting coins, possibly the dirtiest things on the planet, into it?! Eurgh....

    Just like when I ordered a falafel kebab thing at Bestival recently, the woman made it carefully with her hands clad in rubber glove things, but then promptly proceeded to take my cash without removing the rubber gloves. Some people are utterly clueless! Is this not just common sense? Does she think that rubber is somehow impervious to bacteria?

    Are you American or something?
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  • mudcow007
    mudcow007 Posts: 3,861
    Health and safety alert... Isn't that water for human consumption? And you want to start putting coins, possibly the dirtiest things on the planet, into it?! Eurgh....

    Just like when I ordered a falafel kebab thing at Bestival recently, the woman made it carefully with her hands clad in rubber glove things, but then promptly proceeded to take my cash without removing the rubber gloves. Some people are utterly clueless! Is this not just common sense? Does she think that rubber is somehow impervious to bacteria?

    there is a sandwich van that comes around our industrial estate, their drivers always wear those bright blue gloves to serve food.....and to give you your change.....and to drive around in

    i sh*t you not

    doesnt bother me though, i dont buy off em!
    Keeping it classy since '83
  • redvee
    redvee Posts: 11,922
    Will look at the wording on the card. If classed as a challenge tehn there has to be some chance of being able to complete the challenge.
    I've added a signature to prove it is still possible.
  • DrLex
    DrLex Posts: 2,142
    Plastic coin from a child's toy/game? Otherwise, switch in your own weighted lemon as per LiT's plan or spray surface with a can of pipe freeze. Last thought - hang weights (?2 more coins) on thread on either side of the coin, so it's like a set of panniers on a rack and CoG remains below CoB.
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  • Zachariah
    Zachariah Posts: 782
    Are you allowed to jam the coin inside the lemon, or do the rules stipulate it must be resting on the top, outside the skin?
  • kelsen
    kelsen Posts: 2,003
    Try and squash the lemon slightly without anyone noticing before you place the coin on top.
  • Clever Pun
    Clever Pun Posts: 6,778
    no link to lemonpaarty.org?

    for shame on you all
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  • Keith1983
    Keith1983 Posts: 575
    DesWeller wrote:
    Health and safety alert... Isn't that water for human consumption? And you want to start putting coins, possibly the dirtiest things on the planet, into it?! Eurgh....

    Just like when I ordered a falafel kebab thing at Bestival recently, the woman made it carefully with her hands clad in rubber glove things, but then promptly proceeded to take my cash without removing the rubber gloves. Some people are utterly clueless! Is this not just common sense? Does she think that rubber is somehow impervious to bacteria?

    Are you American or something?

    :lol:
    Two things wrong with this.
    1. This is a food hygiene issue not a health and safety one.
    2. The Americans are useless when it comes to H&S and only like making claims for lots of money regarding injuries normally received through sheer stupidity!