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Water's surface tension can support a metal paper clip. An attraction between the molecules in water causes its surface to act in an elastic manner. By photographing it using a grill in front of the light source, the indentation of the surface caused by the clip's weight can be seen. This bending of light is similar to that in strong gravitational fields, as predicted by Einstein's theories.
Identification techniques are increasingly relying on medical technology, or biometrics, to provide more personal forms of ID, which are harder to fake. Some feel that this is an invasion of their privacy.
The popping of a balloon happens too fast for us to see in detail. But high-speed photography reveals what is happening at the time of the pop: The stretched skin of the balloon breaks rapidly and violently.