In this Activity, students use an oatmeal canister to make a pinhole camera, load it with black and white photographic paper, and create a paper negative using the camera. This interdisciplinary Activity combines chemistry and art.
As the raft of bubbles is stressed with the slider, dislocations move into and out of the grains and their boundaries.
An atomic-level simulation shows what happens to the metal bobby pin during the tempering process.
A synthetic diamond wafer and an aluminum disk are held between a thumb and forefinger (to provide heat). When pressed against an ice cube, the diamond penetrates more rapidly than does the aluminum.
Butter is used to glue a piece of pasta to each disk. When the edges of the disks are immersed in hot water, the butter on the diamond melts more rapidly, releasing the piece of pasta.
When memory metal is bent, it deforms. When placed into hot water, the metal "remembers" its original shape.
An animation shows how memory metal can be deformed then go back to its original shape.
A metal bobby pin is heated until red hot, then allowed to cool slowly; this process is called annealing. The annealed bobby pin is very flexible.
An atomic-level simulation shows what happens to the metal bobby pin during the annealing process.
The tempering process, which involves heating a hardened bobby pin then cooling slowly, transforms the brittle metal into springy metal.
