Montshire Minute: Balance

Originally aired during the week of August 31, 1998

Monday

If you have a lot of free time on your hands, perhaps you'd like to take a crack at breaking some of these world records. In 1980, a man from North Carolina balanced seven golf balls, one on top of the other. Without using any glue. And in 1988 in Central Java, Indonesia, 19 people successfully mounted and rode a bicycle. I mean, all at once! And a man in France spent a record 185 days balanced on a tightrope. He even slept while balancing! That guy knows balance! Balance is something that's sometimes difficult for us to achieve, whether we're walking on a slippery sidewalk, or trying to balance the checkbook. Assuming you could use a little more balance in your life, stay with us on the program this week. Maybe you'll learn enough to break the record for number of cigar boxes balanced on a person's nose: 212.

Tuesday

Ever tried to see-saw with a 500 pound gorilla? It's just not a well-balanced situation, is it? But imagine what happens if the gorilla sits closer and closer to the center of the seesaw. At some point your weight, sticking way out on one end, will balance out the weight of the much heavier gorilla that's sitting near the pivot point. And the seesaw will level out. Whether you're aware of it or not, you and the gorilla have discovered torque. That is, the distance from the pivot point, times the amount of force (in this case, the downward force created by your weight). Torque is a rotational motion, and we really put it to work in all sorts of jobs. For instance, turning on a water faucet, or loosening a stubborn bolt. You know you can get really good leverage on the bolt when you push straight down on the end of the wrench.

Wednesday

Throw a baseball into the air and it travels in a nice, smooth arc. Now imagine tossing an irregular object, like a baseball bat it the air. The bat will turn end over end, wobbling all over the place, right? But if you look closely, you'll see both ends of the bat are whirling around one point that follows the same smooth arc as the ball. This is the bat's center of gravity. Pick up the bat, and you'll discover you can balance it on your finger at precisely this same point. Every object has a center of gravity somewhere. But sometimes that point is in mid-air! Take a doughnut, for instance. The doughnut's center of gravity, or average position of all its mass, is at a point in the hole. So you can't really balance it on it's flat side. There's nothing but air there! See Montshire's new exhibit Amusement Park Science, opening Saturday, March 11. It introduces you to concepts of balance and laws of motion!

Thursday

Whether you realize it or not, you perform a pretty amazing feat every single morning, just by getting out of bed. I can tell you're not impressed. Well consider this! In order for you to successfully stand in a upright position, a number of things inside your body have to be working together perfectly. The three semi-circular canals in your inner ear contain fluid. In the same way the fluid in a carpenters level tells us when something is out of whack, the nerve endings in your ear, stimulated by fluid movement, send signals to your brain like "left, left... no, turn to the right... left again. Whoa!" The brain tries to reconcile signals from the ear with other information coming from the eyes, joints, and sense of touch. Without us even knowing it, our bodies are always hard at work just keeping us from falling over.

Friday

For this experiment you will need: 1.) yourself 2.) a friend 3.) a pillow 4.) and 5.) a floor. Got all that together? Good. Now, take off your shoes and stand with your feet together on a carpet. You are now using all your senses to help you stay in balance - your joint receptors, your inner ears, and your eyes. Next, close your eyes. The inner ear and joint receptors are working to keep you balanced. Now... stand on the pillow and close your eyes again. Your inner ear is on the job alone! Ask your friend to notice how much you are swaying back and forth. Chances are, you will be swaying a little bit, though you may not feel it. Your inner ear is "flying blind" trying to keep you balanced without any other sensory information to help out. Beginning March 11, you can see Montshire's new exhibit called Amusement Park Science. It introduces you to concepts of balance and laws of motion!