TRUTH AND NUTS COME TO THE SURFACE

Take a pop-corn bowl. Fill it half with rice. Take hand-full of peanuts. Put on the rice. Mix them well. Now shake the bowl. Slowly, all the nuts will come to the top and the rice will settle at the bottom. This is called 'Brazil nut effect or granular convection'.

Why this happens? There are two reasons.
1. The system wants to lower the center of gravity and to occupy minimum energy level.
2. Small particles easily slip through the gaps between the larger particles and reach the bottom.

In the case of salt and sand. sand rises to the top.
Suppose, you want to reverse Brazil-nut effect, there is a way. Use a 'cone' shaped container. In cone, smaller particles come to the top because the gaps or the space decreases as you go down. The principle can be used for filtering particles according to size.

The plowing of a field always brings up new stones and boulders due to 'granular convection'.
Gravity is the driving force in this 'effect'. Stronger the gravity, faster the convection. Granular convection will be slow on the moon.
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THE EARTH, A SUPER ORGANISM

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A jet of water shooting from a hose pipe will follow a parabolic path. What is the so special about parabola. Y= x^2 Draw a graph for the above equation. It will result in a parabola. This parabola is also called unit parabola. Any equation involving square will yield a parabola. Example: Y = 2x^2 +3x+3 (also called quadratic equation) X= 2 and -2, both satisfies the equation 4 = X^2. Parabolic equations always have two solutions. Any motion taking place freely under gravity follows parabolic path. Examples: An object dropped from a moving train, A bomb dropped from flying plane, A ball kicked upwards. If a beam of light rays fall on the parabolic shaped mirror, they will be reflected and brought to focus on a point. This fact is made use of in Dish Antenna, Telescope mirrors, etc. Inverted parabola shape is used in the construction of buildings and bridges. Because the shape is able to bear more weight. A plane

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Imagine a balloon full of air. The air molecules are moving randomly inside the balloon. Let us pierce the balloon with a pin. The air rushes out. Why should not the air molecules stay inside the balloon safely and ignore the little hole? That is not the way the world works. The molecules always "want to occupy as many states as possible". Hence the air goes out in the open to occupy more volume. The things always goes into disorder (entropy) and the disorder increases with time. The above statement is what we call "second law of thermodynamics". Consider a cup of coffee on the table. Suppose the heat from entire room flows to your cup of coffee, the coffee will boil and the rest of the room will freeze. Freezing means bringing things to order and arrangement. It violates the second law. Hence it will never happen. Hence heat must flow from high temperature to low temperature and not the other way. The air molecules in y

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