Wednesday, 13 April 2011

How my first grade teacher distorted me

Not physically correct

A proper raindrop

I still hate how my first grade teacher have distorted my view of the world.  It still amazes me that they teach creationism in schools in the US (so I am glad I was not educated there).  Like most children I spent some of the time drawing in first grade.  We drew things like a heart, a star and a raindrop.  They say these are supposed to look a certain shape that is in no way resembling of that shape.  I drew it how I thought it might look and the teacher said I have to try again.  After many tries I drew the heart, the star and the raindrop that she wanted.  Fifteen years later I find myself disappointed when I am dissecting a cat in a vertebrate biology class to see nothing like the heart in my grade one class.  
Also I learn that raindrops are nothing like as I drew them in grade one.  Nearly every drawing of raindrops I have seen depicts them as having a sharp upper point. This like many other things in life the first grade teachers are completely wrong. If they had studied a little more physics and a little less (what do first grade teachers study?).  I would not be as confused as I am now.  The surface tension of water acts like a stretched "bag" around the water. Unless some other force is acting, it pulls the water into a spherical shape. When we see droplets of water our eyes see them the tiny droplets as a blur.  With slow motion photography shows that small raindrops are nearly spherical. The larger ones are distorted by the pressure of moving air, but this doesn't make points!  It makes them somewhat flattened. Think of it this way: underwater bubbles are not pointed as they rise, just as falling water drops are not pointed as they fall. 
One might point out that when water drips from a faucet it has a point.  However, the water droplet never actually has a point. Instead it has a narrow neck.  It holds on to the faucet due to its surface tension.  After the neck has snapped, it is yanked back into the falling ball of water. 

If you will excuse me I have to take that failed drawing I got of improperly shaped droplet back to my first grade teacher and complain...