11-04-2009, 07:22 PM
Thank you very much for the introduction to this delightful learning tool!
One thing surprised me. I know that I have seen grains of salt, and felt their edges. It surprised me that human eggs, and some bacteria, are not much smaller than a grain of salt. This might make them visible. But I'd always thought of them as "microscopic," totally invisible to the naked eye.
I was curious how that compared to the thickness of a human hair. I found a reference to fine, thin hair at around 50 micron diameter and thick, coarse hair at around 150 micron diameter.
This makes the human egg around the same thickness as very thick hair, and the human sperm cell about as long as the the thinnest human hair. In other words, individual human sex cells might be just visible.
As someone interested in digital photography, I've read that image sensors typically have pixels sized about 4 to 8 microns across. Interesting to see this is about the same size as mitochondria to red blood cells.
I am trying to wrap my head around the physics of Dewey Larson, but I don't have the math background to fully appreciate it.
Here is another, similar presentation that continues out to astronomy. What an awesomely scaled universe we live in.
http://micro.magnet.fsu.edu/primer/java/...owersof10/
Carl Sagan's Cosmos also had some beautiful explorations of scale.
One thing surprised me. I know that I have seen grains of salt, and felt their edges. It surprised me that human eggs, and some bacteria, are not much smaller than a grain of salt. This might make them visible. But I'd always thought of them as "microscopic," totally invisible to the naked eye.
I was curious how that compared to the thickness of a human hair. I found a reference to fine, thin hair at around 50 micron diameter and thick, coarse hair at around 150 micron diameter.
This makes the human egg around the same thickness as very thick hair, and the human sperm cell about as long as the the thinnest human hair. In other words, individual human sex cells might be just visible.
As someone interested in digital photography, I've read that image sensors typically have pixels sized about 4 to 8 microns across. Interesting to see this is about the same size as mitochondria to red blood cells.
I am trying to wrap my head around the physics of Dewey Larson, but I don't have the math background to fully appreciate it.
Here is another, similar presentation that continues out to astronomy. What an awesomely scaled universe we live in.
http://micro.magnet.fsu.edu/primer/java/...owersof10/
Carl Sagan's Cosmos also had some beautiful explorations of scale.