Tag: dust

Do You Feel Alone? – By Kurzgesagt

By Anupum Pant

If you feel worthless or alone, or both, you probably are looking at things very superficially. It’s time to realize who you are and where you stand in this vast universe.

Today, I’m just going to leave you with a brilliantly animated, science + philosophical video by Kurzgesagt.

(Just that because I’m too tired to write and happened to stumble upon this amazing video which I felt like sharing)

Also, don’t forget to check out their other videos. All of them are brilliant. Yes, I’ve watched them all. [Channel link]

Harmless Flour is an Incredibly Explosive Substance

By Anupum Pant

Background

The next time you are biting off from a bread, pizza, pancake or a doughnut, you should probably take a minute and pay a silent acknowledgement to the people who work in flour mills to bring flour to your homes. Yes, because flour, the seemingly harmless cooking ingredient can be an incredibly dangerous substance – It explodes.

Wait a minute. It isn’t a minor explosion I’m talking about. I’m talking about really big explosions. Read on to know more.

Burning Flour

Flour is almost completely starch (or carbohydrate). Since Carbohydrate is nothing but a large molecule which is essentially a couple of sugar molecules linked to each other, it burns like sugar. And everybody who has tried burning marshmallows on a candle knows how easily sugar catches fire. Agreed, carbohydrate isn’t as sweet, but it is just like its cousin sugar when it comes to flammability.

So, that is how flour can catch fire. But what is it that makes it bring down full-sized buildings?

Flour in air

Flour in your kitchen’s flour container can be a very boring thing. The fun starts when the tiny flour particles are suspended in air.

Flour particles suspended in air, or for that matter, almost anything suspended in air that can catch fire, is a dangerous thing. For example, look at one of the most hazardous situation you can have in a coal mine – There is coal dust around and accidentally there is a small sparkle around it. The whole place explodes like a bomb. This has resulted in some of the worst ever mining accidents in the history.

Such explosions happen because anything that is in powdered form and is suspended in air, has a far more surface area exposed to oxygen per unit weight, than normal lumps of the same substance. This is true for industrial stuff like powdered coal, sawdust, and magnesium. Besides that, mundane substances can explode too – like  grain, flour, sugar, powdered milk and pollen.

All it takes to cause a disaster is a suspended combustible powder and a little electric arc formed from electrostatic discharge, friction or even hot surfaces – A little spark is enough.

Such settings are common in flour mills, where there is flour floating around literally everywhere. This is what caused a giant explosion in a flour mill in Minnesota on May 2nd, 1878, killing 18 workers. But that was more than 100 years ago. Kitchens are relatively safe because you don’t have enough flour in the air to catch fire and produce great volumes of air that are enough to cause an explosion.

This happens even today. From the year 1994 to the year 2003 there have been 115 such reported explosions in food processing industries in the US.

[Source 1] [Source 2] [Source 3]

Experiment

The following is a simple experiment you can do at home (obviously with adult supervision) to understand the explosive nature of a harmless cooking ingredient. [Video]

What you need: Safety glasses, Tin can (with lid), Candle, Matches, a long Straw and fine white flour

  • Take a tin can, one with a relatively tighter lid. Make a hole at the lowest point in the side wall (just enough to fit in a straw).
  • Open it up and put in a handful of flour inside it. Now is the time to put on your safety glasses.
  • Now, burn a candle and carefully place it inside the can.
  • Close the lid, insert the straw into the hole. Now blow at the base of the can, in a way that flour stirs up inside without extinguishing the candle.
  • Watch the lid pop up 10 feet into the air.

The Evil Lunar Dust

By Anupum Pant

Space exploration is a tough job. Besides a myriad of challenges that have to be dealt with, space equipment and astronauts travelling to places like the moon or mars, have to deal with a peculiarly wicked foe – The dust.

This isn’t the kind of normal dust we deal with here on earth. ‘Downright evil’ is the phrase that describes the dust on moon! We may not realize it, but lunar dust is a filthy thing and causes a lot of problems. Of course, the dust on mars is no better.

Back in 1972

For instance, let us see how moon dust makes things complicated for engineers and astronauts.

Most of the upper surface of the moon is covered with a mixture of loose material comprising of dust, soil, rocks and pebbles (and other random stuff too). Normally, at places, this layer of mixture ranges from 4 to 6 meters in thickness.

The fine part of this mixture is called the lunar soil and is significantly different from the soil found on earth. It is present almost everywhere on the surface of the moon and is a result of breaking of rocks into small particles by meteorite and micrometeorite impacts; also there is no wind and rain to soften the pieces. This is the part of that loose stuff which is known for causing immense troubles.

The dust is super-fine and extremely hard. You can think of it as collection of little shards of glass. Despite being completely dry, it sticks to everything it touches and as it is super-fine, it can get into tiny creases. If inhaled, it can be toxic; like millions of tiny sharp shards piercing into the inner walls of your respiratory system. A tiny amount of it can eventually kill a full grown man.

Back in 1972, the Apollo 17’s crew learnt this as soon as they stepped out. The dust started clogging their air vents and started dropping the pressure. When returning to their space capsule, Jack Schmitt and Eugene Cernan forgot to brush off the dust. They were stuck with it for the whole time during their journey back home. Some of the dust went airborne in the craft and Schmitt started complaining of congestion. Fortunately, the amount was too small to hurt them a lot. Soon the symptoms subsided and space agencies learnt a lesson – Find a way to deal with the lunar dust.

On mars: Dust on mars can travel places due to dust storms and cause more problems.

Solution

Scientists at NASA found a great way to deal with this dust using an electric zap. They were able to develop electrical fields which can clear about 99% of the dust from the equipment. These dust shields will be tried on in the year 2016.