Brazil Nut Effect – Saving Lives in Snow

By Anupum Pant

The effect

Have you ever noticed that the larger nuts (Brazil Nuts) in your Muesli boxes or bowls end up on the top? It turns out, scientists have a name for this effect. They call it the Brazil Nut effect or Muesli Effect. Well, actually scientists prefer to call it Granular convection.

If you haven’t heard of Muesli, think of a bowl full of random nuts. Or Indians could think of the Haldiram Navratan Mix – A popular snack mixture that contains several types of fried ingredients in various sizes. Irrespective of the kind of snack or even a mixture of sand you think of, it shouldn’t come as a surprise to you that the smallest of particles always end up at the bottom of a mixture when shaken enough.

If you think there is nothing cool about this effect, you are probably picturing it wrong. Watch this video where, on shaking, big marbles magically come on top of a rice heap.

Research studies

Normally, isn’t it common sense to assume that the largest (presumably the heaviest also) particles should end up at the bottom? Such is the counter-intuitive motion of particles in granular mixtures that it gives scientists a great insight about the real physics that goes inside. So they love to study more about this phenomenon.

This effect is so popular among scientists that some have studied it in martian and lunar gravity simulations. To do this they had to go on a plane that moves in parabolic arcs to simulate a specific reduced gravity conditions – A reduced gravity aircraft.

It saves lives

In the snow, sport persons or people taking part in extreme sports carry an avalanche safety bag with them.  On a free ride down a snowy cliff, sometimes these people get caught in avalanches. Being on top when the avalanche has settled helps the rescue teams find them. The avalanche safety bags are huge when they are inflated. And thanks to the Brazil Nut effect, these big bags attached to the sports person, often end up on the top.

The Reverse Brazil Nut Effect

And sometimes there is a reverse Brazil nut effect. Meaning, if certain conditions are met, the largest nuts can end up at the bottom of a container.

The shape of the nuts, shape of the container and the relative sizes of nuts plays a role in determining if the effect reverses or not. As a simple example, using cone shaped container reverses the effect.

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Tritonia Khaleesi – New Slug Named After the Mother of Dragons

By Anupum Pant

Wish you a Happy 2014

It’s the last day of the year! What am I doing?
I’m writing this blog-post while everyone in the city is partying. That might sound like a sad thing, but I like to think of celebration as something that isn’t the same for everyone.
For instance, think of the sea slugs for a moment. The last day of the year means nothing to them. Even when it is party time for everyone else, they do the thing they do every day. Although it makes sense here, sea slug is not to be confused with the first generation British surface-to-air missile.
Anyway, I wish all of my readers a very happy and a successful 2014. If you need some help with sticking to New Year resolutions, you could check this out – [Help!]

So, talking about sea slugs – A sea slug can be thought of as a type of a snail, without a shell living in the sea. But, why am I talking about sea slugs suddenly? There is a reason.

A new sea slug

Felipe de Vasconcelos Silva, Victor Manuel De Azevedo, and Helena Matthews-Cascon from the Federal University of Ceará discovered a new kind of sea slug off the coast of north-east Brazil. They decided to name it Tritonia khaleesi.
If it doesn’t ring a bell, it is probably because you do not watch Game of Thrones on TV. They named it after the mother of dragons, Khaleesi, from the Game of thrones – a fantasy drama television series which is an adaptation of A Song of Ice and Fire, George R. R. Martin’s series of fantasy novels.

Why did they name it that?

If I may quote the scientists themselves, their words pretty much answer this question:

The standard of the silver band on the back of the slug reminds braids Khaleesi of silver hair, especially in the last episode of the first season of the show. Besides silver color, the species is one of the smallest sea slugs, as well as Khaleesi is also described as low and new.

What did you learn?

Well, Several things! Things like:

  1. Scientific names can be after character names from TV shows or fantasy novels.
  2. The British called their first generation surface-to-air missile – Sea Slug.
  3. New species are being discovered even today. BTW, it is estimated that 86% of the species still living on earth are still waiting to get discovered.
  4. And of course, the new sea slug is named after Khaleesi.
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