random tree
I was coming home from soccer practice today, and I liked the way this tree looked. I took a picture. Just keepin’ the blog alive.
May 30, 2009
May 25, 2009
PhysMo
I remember using some video motion analysis software in school for some of my physics classes, and I wanted to see what is out there for people to use for random purposes- I found a free open-source program geared toward high school science classes. They call it PhysMo, and although it doesn’t appear that anybody’s done anything to it since 2006, you can still download it.
Here’s a link:
http://physmo.sourceforge.net/
I recorded a video of myself dropping a juggling ball in front of a closet, and used mouse clicks to define a distance on screen to define the scale, then clicked the approximate center of the ball in each frame of motion video. With my digital camera set to capture 60 frames per second I found the acceleration of the ball to be about 11 meters per second squared. There was a lot of noise in the data at the beginning and end of the clip. I tried it again with a 30 frame per second clip, and the acceleration came out to about 9 m/s^2.
Neither of these are very accurate, but if the video was reasonably clean, i think you could get better than 5% accuracy. The ball was moving somewhere around 4 m/s by the time it hit the ground, and it really did look like a blur. This might be more useful if I had a different video camera and brighter light.
