Interesting Physics - Photographs

Creation of drops

The process when a drop of a liquid separates from the rest of the liquid is very complex phenomenon that is influenced mainly by gravity and surface tension. We could observe different phases of this remarkable and beautiful process using a stroboscope. We were flashing at a drop of milk and captured the scene with a camera with an open shutter. The first picture shows several phases of the drop fall after it has separated (the small droplet "belongs" to the drop under it, not above it). For taking the photographs in the second row we were moving the device from which the drops were falling, which prevented overlapping of the individual snapshots. We can see that several drops are created during the separation process. This is caused by the instability of the thin neck due to the surface tension that tries to narrow the neck at several places. In the last picture the LEDs of the stroboscope can be seen.