All the air and water on earth - Illustrated

Been a long time since I´ve posted anything, so here comes two posts in the same day to compensate
Found a fascinating computer modeling of all the water on our earth and air in our atmosphere illustrated as spheres on top of the earth.


The water on earth is the sphere to the left, and the air is the one to the right. This includes all the water in the oceans, seas, ice caps, lakes and rivers as well as ground water, and that in the atmosphere.
You can either be shocked at how little water and air there is, or just how big the earth is. The air sphere has a diameter of 1 999km, while the water is only 1 390 across
And for those of you who want to see a little bit of rogue theory on how the earth is actually expanding, tune in here:
http://www.youtube.com/watch?v=VjgidAICoQI
Very cool graphics on the tactonic plate movements

And finally: The sphere of our human mass (with some assumptions)
Asumptions:

6.7 billion humans in the world

Average mass of a human is approx 65kg (Wikipedia says that the mean for the UK and USA is around 75kg; I assume most of the world is lighter than them)

The mean density of a person is 1g/cm3
So humans mass a total of 6.7 billion people x 65kg/person = 4.355x10^11 kg.
At 1g/cm3 this mass takes up 4.355x10^11 litres = 4.355x10^8 cubic meters.
Now we plug this value into the formula linking the volume of a sphere with its radius:
Volume = 4/3 * radius^3
Therefore
Radius^3 = Volume / ( (4/3) *pi)

Radius^3 = 4.355x10^8 / (1.3333333 x pi)

Radius^3 = 1.0397x10^8

Radius = 470.21 meters
Diameter = 940.43 meters
The sphere of all living human bodies would therefore be a puny 1.8KM across – wouldn’t even be seen on the map I found.

Source: http://www.telegraph.co.uk/connected/main.jhtml?xml=/connected/2004/03/31/ecfvos31.xml

Ears popping in train tunnels

A friend of mine recently went to Japan and the took the bullet train. Going several hundred km/hr he experienced a fairly considerable popping in the ears (or propper i ørene as we like to say in Norway).
Now why does this happen?
Curious George took the dive and the easiest way to think of it is imagining that the tunnel is filled with water. When the train enters the tunnel, the water has no-where to go, and is pressed in front of the train, while some escapes "backwards" - this creates a suction in the train, just like what happens when you open your windows going 90 mph - your ear pops and maps and papers go straight out the window.
So when a train hits a tunnel, the accelerated air-flow around the train creates a vacum causing your airs to pop. Just like it would when you are on an ascending airplane.
An air-tight train would solve it, but this is costly and dificult to make. You can also design the tunnel to reduce this effect - ex through air-vents (though if the airvents are too big and too far apart it would feel like you go in and out of a tunnel all the time) or just a bigger tunnel, so that there is less pressure-buildup infront of the train.
The english channel tunnel is an excellent solution to this. Being 30 miles and under water, the "Chunnel" is actually two seperate tunnels connected by cross passages. This greatly improves the air pressure problem.
George says Hona sainara and good luck on ear train popping