Sinking a Granular Raft

Sinking of light intruders in a shaken granular bed.

We present an experimental study of the displacement of a light intruder immersed in a vibrated granular bed. Using high speed video we resolve the motion, during one cycle of oscillation, of a cylindrical object inside a Plexiglas box partially filled with grains. We report experimental evidence that, in the absence of convection, at least two forces are behind the intruder's motion: an air dr...

Sinking of a horizontal cylinder.

We study the sinking of a dense cylinder initially supported horizontally at an air-water interface and then released. The sinking motion is studied experimentally and agrees quantitatively with a simple hydrodynamic model of the process. In particular, our model predicts that the time taken for the cylinder to become immersed in the liquid should be tsink approximately theta((lc/g)1/2), where ...

Sinking treasure

social engagements. With the Bologna system, everything is fitted to match a 40 hour per week work schedule for the entire year allowing only for 6 weeks of holiday and one week of illness. Many students are now protesting against this reduction of university to a school-like system. Students also protested against tuition fees, which have been introduced only recently in a break with a long tr...

That sinking feeling.

Y ou are doing a breast reduction. You have chosen a vertical flap and inverted T incision. You like the vertical reduction and medial pedicle because there is a shorter incision , but you think there will be too much skin excess, so it will be better to excise it now. For some reason, every time you do the inferior pedicle the base of the pedicle becomes thin and narrow. This worries you. You ...

That sinking feeling.