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A Body in Motion May Not Want to Go

© Linda Bond

Okay, so I just got off one of the new smaller buses our transit system opted to buy (to appease critics) and, guess what, THEY RIDE LIKE A SKATING BRICK!!! Now that I've got that out of my system...

Once Upon a Bus Ride

As we skated around in the pot holes, chuck holes and just plain street holes, I was soon reminded of the effect of centrifugal force on a body that wishes to remain inert. In other words, I wanted to stay put in my seat and the suspension on that bus wanted to send me flying around - up, down, sideways - it didn't care. Just so long as I didn't stay put in my seat. Centrifugal force is like that. Actually, for centrifugal force to be at fault, the bus would have to start spinning around like a top, but close enough...

Then, for some strange reason, I got to thinking about what would happen if the planet's skin suddenly came to a stop and all of the stuff (like cars, buildings, people) on the surface kept going. Wow, what a mess! But that's what would happen, of course, because once an object is moving (we are spinning around along with the Earth after all), it wants to keep moving. There's a "law" about that somewhere - an object in motion wants to stay in motion until acted on by another force of equal or greater power - or some such thing. Anybody out there know what the actual quote is????

So back to my bus ride. I was going along with the bus heading nicely down the street when all of a sudden the bus went down in a hole and I stayed up. Then I began to fall down (due to gravity) and the bus came back up to meet my bottom. Ouch! Between centrifugal force and gravity, that bus had me coming and going...

Experimental Strawberries

And then....... I remembered last night when I washed some strawberries to make dessert. To do this experiment, you will need:

• a smallish container (I used an empty cottage cheese pint)
• a few small floatables (I used strawberries)
• some water (less than what the container will hold)

Now, put your floatables in the container and add the water. Leave about an inch of space between the top of the water and the rim of the container. (Trust me, you'll wish you had if you don't.)

Next, holding the container in your hand, slowly begin to rotate the container in a clockwise motion. NOT THAT SLOW, SILLY! Then try a counterclockwise motion. (No special reason, it just adds to the suspense.) Then try a SLOW back and forth rotation sort of like a washing machine uses on your clothes. As you do this experiment, keep your eye on the floatables. What do they do?