Challenge your friends!
If you don't have the brawns for arm wrestling, outwit your friends with your brain...and science! Use these six bets and challenges to prove yourself, and maybe even earn a little money. The bets are things that look simple to do, but are impossible, and the challenges are tasks that look hard, but have a simple trick to them.
1. Lift your foot
The Bet: Bet your friend that he or she can’t stand with her her left shoulder, side and foot against a wall and lift his or her right foot without moving away from the wall.
The Science: When you lift your leg, your body has to lean slightly the other way to keep you balanced. Since the wall is in the way, your friend won’t be able to do it without falling over.
2. Draw a perfect circle
The Challenge: See who can draw the most perfect circle without using anything other than a pen and piece of paper.
The Trick: Place the knuckle of your pinky finger where you want the center of the circle to be and lightly touch the pen to the paper. Then, keeping your knuckle and pen where they are, slowly turn the piece of paper.
3. Coin Balancing
The Challenge: Place a playing card over one side of the rim of a glass of water and challenge your friend to balance a coin on the outer side of it. The card will always fall off under the weight of the coin.
The Trick: Fill the glass up to the very top with water first. The surface tension will be enough to keep the card flat as you balance a single coin on the other side.
4. Superglued Fingers
The Bet: Have your friends place their two palms together and then bend their middle fingers inwards. Bet them that they won’t be able to “unstick” their ring fingers.
The Science: The tendons in your ring and middle fingers are connected, which means that you can’t move your ring finger if your middle one is folded down. You can also do the same trick by placing one hand, palm-down, on a table with the middle finger bent under. You won’t be able to move your ring finger.
5. Double Straws
The Bet: Bet your friend that he or she won’t be able to drink out of a glass using two straws, one that ends inside the glass and one that ends outside it. Blocking a straw with your tongue is considered cheating.
The Science: Normally when you drink through a straw, your mouth becomes like a vacuum pump—if the air pressure in your mouth is lower than the air pressure in the atmosphere, the air will push down on the drink and push it up the straw. However, since your friend also has a straw leading outside the drink, it makes it impossible to form a vacuum.
6. Paper Blowing
The Bet: Place a small ball of paper in front of a bottle lying down on a table. Bet your friend that he or she won’t be able to blow the ball into the mouth of the bottle.
The Science: When you blow towards the bottle, you increase the air pressure inside it, which leads to air flowing out. This air pushes the ball of paper away from the opening.
Check out some more science tricks from The Science Explorer.