Thanksgiving Table Tricks –Entertain Your Guests with After Dinner Science

The meal is wrapping up, the dishes are in the sink and everyone is sitting around the table waiting for the pie to come out. Now is the perfect time to stand up and amaze your family with a few science “tricks” using materials found in your kitchen.

Remember that you shouldn’t try these experiments at home…do them at a friend’s home.

Singing Glasses and Move a Match with Your Mind

If you like to annoy all of your dinner guests by running your finger along the rim of a wine glass to make it sing, you’ll soon have your friends convinced that you can move objects with your mind. Magicians and psychics are able to move an object with their mind. You will too when you learn this first table trick.

You will need two identical wine glasses, stick matches or toothpicks and water.

Fill each glass with equal amounts of water (about half-full seems to work well). Hold the stem of the glass with one hand and dip the index finger of your other hand into the water. Rest your finger on the rim of the glass, press down slightly, and rub it all the way around the rim without stopping. Keep going in a circular motion along the lip of the glass while maintaining the pressure, and, in almost no time, you’ll have displayed a newfound musical talent.

Once you’ve mastered the art of making the wine glass sing, do the same thing with the other wine glass. You want the tone from each glass to be the same. This means that you will need to adjust the amount of water in each glass so that the tone is exactly the same.

Here’s the fun part. Rest a stick match on the rim of one of the glasses. Position the second wine glass close to the first one, but make sure they’re not touching. Dip your finger in the water and make the glass without the match sing, but don’t take your eyes off the match. What? The match moves! How does that work?

The movement of the match is caused by a sympathetic vibration. Because you added equal amounts of water, the second glass vibrates at exactly the same frequency as the first. The sound waves produced by the first glass travel in every direction. When those sound waves reach the second glass, the glass begins to vibrate as well and the match moves.

Tablecloth Trick

The classic “whip off” the tablecloth trick is a must for any aspiring science demonstrator who wants to be amazing! The challenge is simple – whip the tablecloth out from underneath the place setting without destroying the China or the meal.

First you will need a piece of smooth, ironed material without a hem but with a straight edge. Place cups, plates and utensils on top of the tablecloth and close to the edge of the cloth.

Grab the ends of the tablecloth with both hands and quickly pull it straight down and away from the table. Pull down, not out.

This is Sir Isaac Newton’s First Law of Motion. Inertia is the tendency for an object at rest to remain at rest until a force acts upon it. The dishes on the table will not move unless an outside force moves them. Whipping the tablecloth out from under them keeps the dishes at rest while the tablecloth is in motion.

**Don’t experiment with mom’s best dinnerware. At least for starters and until you get solid with performing this trick, use plastic or unbreakable dinnerware and do it over carpet.

Genie in a Bottle – Prayer Vase

You can invite a magical creature to your Thanksgiving dinner. Just keep in mind that the genie in the bottle is very shy. If you try to get the genie out of the bottle by tickling her with a rope, she will get angry and hang onto the rope. Turn the bottle upside down and the rope will hang from it. Turn it right side up and the bottle will hang from the rope and “float.” On command, the genie will release the rope.

For this trick you will need a small bottle with a long neck like an old fashioned soda bottle., a short length of cotton rope (about 1 foot long) and a small piece of aluminum foil (about 6 inches square.)

Depending on the type of bottle you use, you might need to either paint the bottle to make it opaque or cover the bottle with something so the audience cannot see what’s happening inside the bottle.

You’ll also need to make the secret genie… a small ball of aluminum foil! Crumble the foil into a ball that will just barely fit through the mouth of the bottle.  Don’t squeeze it too small, but make sure that it doesn’t get stuck when you put it into the bottle and pour it out again. This small metal ball is what does the magic.  It’s the genie!  When you’re satisfied that it’s just the right size, place it into the opaque bottle and leave it there – no one will suspect anything.

Remove the rope from the bottle and display both. Don’t shake the bottle or the genie will rattle. Tell everyone the story about the genie not wanting to come out of the bottle. Place one end of the rope into the bottle.  Push it all the way down until it just touches the bottom.

This is important… with your left hand holding the bottle, and your right hand holding the rope in place, turn the bottle and rope upside down.  The genie will fall toward the neck of the bottle, and by gently tugging on the rope, the genie will become stuck between the rope and the neck of the bottle. When you feel this happen, you can let go of the rope with your right hand.  Voila!  The genie is hanging onto the rope making it appear that it is floating in space.

Grasp the rope, once again, with your right hand, and while applying just a tiny bit of tension, turn the bottle and rope right side up. You should still be able to feel the genie hanging on to the rope.

Explain that the genie is strong enough to make the bottle float, as well.  Let go of the bottle with your left hand and show it floating at the end of the rope.

Finally sneak the genie out of the bottle so no one sees it.

The genie in the bottle works with friction. Friction is the rubbing of one object or surface against another. The rough surface of the crumpled aluminum ball (the genie) provides adequate friction between the rope and the bottle to keep the rope from slipping out.

For more Thanksgiving Table Tricks and After Dinner Science, visit us at SteveSpanglerScience.com.

Susan Wells is a native Colorado mom to two girls, ages 6 and 10. She loves to find the learning in everything. In past lives, Susan has been a symphony bassist, sound engineer, news web producer and web developer. She currently works for Steve Spangler Science in web marketing, social media and blogging. She also blogs at TwoHandsTwoFeet.com.

Author: Susan Wells