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I want the cat
Steal the cat for me
I need the cat
Give me the cat
I got a dark secret and the cat is the key.
With my power to control the wind and the evil cat i will rule the world and exploit everyone else.
I need your help.
The cat!!!!

Adina Klink

Music and Silence

Music and Silence are two sides of the same coin. There is no music without silence and no silence without music. Music consists of beats with varying lenghts, spaced out by silent gaps, if there were no silent gaps, then there would only be constant sound and it would become noise. This means that we are not only attracted to particular sounds when we listen to a song, but mostly to the contrast between different sounds, and a melody is made as much of sounds as it is made of silence. But it’s not only in music that contrast plays the fundamental part, take paintings, what is a painting? a painting is a mix of colors that have contrast between them, if there is no contrast, then the painting is not interesting, blue contrasts with orange the most, purple contrasts with yellow the most, red with green and so on, but a painting is also composed of light and dark shades, if there is no variation in light and shadow, it will look flat and lifeless, it is the play of light and shadow that makes a painting look three dimentional and amazing, rather than flat and dull.

This is one of the fundamental laws of the universe, that eveything comes in opposites so that we can know the difference between anything at all. If we were ecstatic at all times, we wouldn’t even know what ecstasy is, we would be indifferent to it. We need dark times so that we know when the light has come. There is no point in resisting darkness, for in doing that, we would be resisting light too.

“People think the world is light, so they push away the darkness, but if the world was darkness, would they push away the light?” – Gincola

How to calculate the radius of the Earth using a water well

In about 276BC, it was known that at noon, in the city of Syene, the sun would shine directly over a water well, meaning its rays are perpendicular to the water. At the same time in Alexandria, the sun would cast shadows on objects, meaning the angle of the light rays were different than 90 degrees to the ground.

Eratosthenes, a greek scholar, knowing about this, asked a man to walk the distance between the two cities and record it. It was about 787Km.

He then measured the angle that the sun rays made with objects on the ground and found it to be approximately 7.2 degrees.

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Now the way to do it is:
We zoom into the triangle that Syene, Alexandria and the centre of the earth make:

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Now we use a bit of maths: the radius of the Earth is called the hypothenuse of the triangle, and it is the distance we want. Let R be the radius of the earth, then 787/R = Sine(7.2)
Hence R  = 787/Sine(7.2) and Sine(7.2) is about 0.125 (you can use a calculator for this). Hence R = 787/0.125 = 6296Km. The accepted distance nowadays is about 6 378.1 Km. How close he was and what a genius he was.