A spring called: Drop of waterWritten by K.A.Cassimally
Do you know what happens when a drop of water hits a non-absorbent surface? Yeah you’re right (if you don’t have answer, please re-read title of this column), drop bounces upwards.A French scientific team from Collēge de France have studied scene carefully with a camera that took 40000 images per second. Here are results: At first, when it hits surface, drop flattens. Then, it bounces up due to movement energy it had when falling down. The drop will continue going upwards eventually taking shape of a needle. Afterwards, drop falls upon itself, into itself. It thus takes shape of a pancake (again) but this time, drop is in midair. This phenomenon is different to a drop falling on other surfaces as in this case, drop crashes on surface leaving only a small quantity of water to bounce up. Physicists have also found out that actual speed of a drop influences its deformation but not time taken for it to get in contact with surface. This actually depends upon mass of drop.
| | Space PollutionWritten by K.A.Cassimally
I bet you haven’t ever wondered about pollution of space. Yes, man started polluting space ever since Yuri Gangarin (first man in space) saw Earth in its entirety.Earth is not only orbited by satellites but also by paint particles, pieces of glass and even apparatus used by astronauts in past. These may be small (that’s what we think – I mean maybe there’re not) but note that if ever a spanner were to hit an astronaut’s face shield, latter would break down into fragments. The astronaut would, for his part, go straight up to heavens (or down in hell) and there would also be even more pollutants in space (the shield fragments). Now, for those of you who have ever bothered to reflect upon space pollution, did you know that microscopic fragments also make up space pollutant family? I didn’t until I read an article (link below) from The Guardian newspaper. Anyway, where was I? Yeah, there are even more things out there that are considered as pollutants. I read about particles invisible to human eye and undetectable by Earth radars. Best thing though: they have explosive power of a bullet!!! With more and more satellites, probes and men in space, no doubt that pollution is going to rise. We really have to prevent this. How? Till now, space pollution has not proved to be a major threat to us, inhabitants of earth. So, naturally there does not appear to be any hurry to find a solution. NASA though has put a small probe in a swarm of space debris so as to know them better. But as I just said, nobody is really caring about space pollution right now although I should think that in some fifty years (ok, maybe I’m exaggerating), this may well transform into one of those many threats to life on Earth!
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