I thought I knew a thing or two about the laws of motion, so one day I decided I was going to try out the classic tablecloth trick. You know, the one where you quickly pull a tablecloth from under a bunch of stacked water glasses? Easy enough, it was just overcoming friction, right?
Wrong.
I got soaked more times that I want to admit even after using a brand new tablecloth fresh out of the package. So what gives?
Well, I’ll let you in on the secret even though centuries of magicians are collectively telling me not to but…. you’ve got to cut the seam off the tablecloth to make sure you have a smooth pull. You can thank me later when you don’t get soaked like I did!
What you need: Plastic cups of water, plastic plates, an old tablecloth
How you do it:
- Cut the seam off the tablecloth so there is no hem
- Lay down the tablecloth and place the plastic cups water filled cups on top of the plastic plate. (If you are really brave use glass dishes but I’m not that confident yet!)
- Quickly pull down on the tablecloth so you overcome the friction of the cups and plates without worrying about it getting caught on the seam.
- Beam that you are not only a magician – but a scientist!
What’s the science:
Newton’s First Law of Motion states that if an object is at rest it stays at rest and if an object is in motion it stays in motion until acted on by an outside force. For this trick, that means if you pull the tablecloth slowly the dishes will want to to stay resting on the table due to friction. But the trick is, if you do a quick pull with the right tablecloth and overcome friction, you will leave the cups and plates unscathed and you will be dry!
We hope you have fun impressing your kids and friends with this science magic!
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