Gather up a few pieces of silverware and some other odds and ends as you prepare to amaze your dinner guests with this gravity-defying trick. It's a guaranteed hit at your favorite restaurant. You'll either get a free dessert or you'll get kicked out. That's the price you pay for stardom.
- Two forks
- Glass of water
- Wine cork
- Matches (adult supervision is required)
The challenge is simple: balance two forks on the edge of the water glass using only a toothpick. Yes, it's a balancing act with a most interesting solution to the puzzle.
- Start by pushing the forks together (technically referred to as wedging the tines of the forks). This is probably not the best thing to do with your most expensive forks.
- This next step takes some practice and patience. Balance the forks on your finger to find the middle point. This is where the toothpick should be inserted between the fingers (tines) of the fork.
- The next part is also tricky but you can do it. Carefully rest the toothpick on the rim of the glass. Just slide the toothpick back and forth along the rim until you think you've found the perfect balancing point. Slowly pull your hands away to reveal the amazing balancing fork contraption.
- Once you've mastered the balancing, you're ready to do a little showing off. Strike a match (that's the job for your adult helper) and burn the end of the toothpick that is hanging over the inside of the glass. To everyone's bewilderment, the toothpick will burn down to the very edge of the glass but the forks will not fall. It's the ultimate balancing fork act. Prepare yourself for a standing ovation!
The Cork-Fork Mystery
Some balancing fork enthusiasts find this variation a little easier. Give it a try.
- Push the end of the toothpick into one end of the cork. Be sure to position it in the very center of the circle, but you don't have to push it in too far.
- Carefully push one fork into the side of the cork towards the bottom. Be careful not to poke yourself (it's a great job for that adult helper who is begging to help out).
- Push the second fork into the opposite side of the cork directly across from the first fork. Try to make the cork-fork contraption as symmetrical as possible.
- Try to balance the end of the toothpick on the tip of your index finger or in the top of a bottle. Don't be surprised if your science art balances in an unusual position. Remember, you're trying to find the center of gravity just below the balancing point.
- The toothpick does not have to be positioned in the bottom of the cork. Try pushing the toothpick into the side of the cork at the bottom to discover a new center of gravity.
How Does It Work?
The secret to this science stunt lies in your understanding of the concepts of center of gravity and stability. The center of gravity of any object is the point about which you can balance the object as if all the masses were concentrated or gathered at this point. In other words, it's the point at which the object balances from left to right, front and back, and top and bottom. In your balancing fork act, the center of gravity is directly below the spot where the toothpick rests on the rim of the glass. If you look closely at your balancing fork-art, you'll notice that the fork handles are positioned below the toothpick. This actually puts the center of gravity directly below the point where the toothpick is balanced (called the pivot point). Here's where it gets really strange: the center of gravity, where the forks balance front and back, left and right, top and bottom, is actually hanging in mid-air.
Did you know a circus tightrope walker often uses a long stick for balancing in the same way as the forks are used in this experiment? The real secret is not to give up or get frustrated if the forks fall. Just rebuild it and try again. Once you've mastered the balancing act, you'll be the hit of any dinner party.
- WOW!!! Review by Rebecca
I'm only in 6th grade but we did this experiment in class the other day with our science teacher.It was hard to get the forks balanced,but we got them to stay and it was TOTALLY COOL!!! :)
(Posted on October 7, 2009)
- RE: Balancing Nails Review by Steve
John - You're so kind to write. Thanks for the kind works… and I hope you try the nail demonstration. We've shared the detailed instructions online at http://www.stevespanglerscience.com/experiment/00000083 I love the version that you mentioned using the forks and toothpick. I also have this one online - you might want to see if your version is different. You're right… it's a great demonstration of the center of gravity and torque. http://www.stevespanglerscience.com/content/experiment/00000117 Thanks again for watching.
(Posted on January 21, 2010)
- Amazing!!! Review by Peter
Its hard to believe the explanation for how it works!!!
(Posted on March 26, 2012)
- AMAZING! Review by Grandma Pam
Looking to amaze the grandkids, I found this table trick and tried it! Success the first time! Thanks!
(Posted on November 21, 2009)