Monthly Archives: January 2009
Moving in Stereo
Life’s the same, except for my shoes
Stereograms! Make Your Own 3D Camera for $15 or Less
If you happen to have two digital cameras, you can skip some of the steps, like getting the film developed and scanning the pictures. I was able to get my hands on a second camera; I found that butt-end joining got the lenses close together. I also tried side-by-side, using some optics posts and attaching to the camera tripod mounts. Unfortunately I did not have a third camera, so I can’t show the full rig.
Here is a laser table stereogram. I tested this on a few people, and not all could get it to work. But I can, and that’s good enough, for I am the benchmark for many things.
Also, you can see that the two pictures appear to diverge from each other, an example of the leaning tower illusion
Candygram for Mongo!
Mongo, in this case, is a trebuchet. Mongo flings fireballs.
I haven’t named mine.
Lazy Nation Fears Obama Will Create Millions Of Jobs
It's Cold in Here, Mr. Bigglesworth!
Experimental insights: Leak detection
How do you make a seal which does not freeze up at Liquid Helium temperatures? The trick is to use the extremely malleable metal Indium – which remains slightly squishy at low temperatures. Indium is seriously fun to play with, it’s a bit like metallic plasticine.
Peer Pressure
C’mon … we’ve all done it!
Just about anyone with access to liquid nitrogen has dunked things and smashed them.
Cheez Wiz is a Condiment?
Got Stress? It Makes Me Tensor and Tensor!
Everyday physics: the stress tensor
This is very similar to the notion of pressure, as described in the previous post on flotation. Indeed, the units of stress and the units of pressure are the same. The main difference, however, is that the stress is more directional than pressure. So in the picture of the cables above, the force is proportional to the area in the yz plane (the cross sectional area), while the force points in the x direction. However, if we though about it in the vertical direction, the cables are not that good at transmitting force in that direction, so we would expect that the force per unit area going upwards is different. This is on contrast with pressure that goes into all directions at once.
Pictures at an Inauguration
No surprise that The Big Picture has some great photos of the inauguration.
The Inauguration of President Barack Obama
I stayed indoors and watched on TV. No way I was braving that throng.
Multiplying by 1
Unit conversions for mere mortals at Dot Physics