WHY NO BLACK FLOWER?

An artist may say 'black is a colour'. But physicist says, 'black is just a absence of light. A green leaf absorbs all the colours in the sunlight except green. When it reflect only green light, it looks green. A black shirt will absorb all the light and emits none. Hence it looks'black'. Consequently the wearer will feel warm.

Flowers normally have soft petals. Hence they have short life. Had there been a black flower, it would absorb all the solar radiation and whither quickly. The flowers normally have white or bright colours.

Solar panels, umbrella, solar cooker are black so that they can absorb the sun's heat fully.
There is star with infinite density, heavy mass and enormous gravity. It attracts and absorbs everything due to its immense gravity. Even it swallows light. Hence it is called 'black hole'.
Take black iron metal. Heat it. First it will turn yellow, then orange, red, blue, and white. So a black body is good emitter also. The 'black body' helped to discover 'photons' and gave birth to 'quantum physics'.
Ultraviolet light is called black light since it is invisible. Black light can be used to detect counterfeit bank notes. Some features in the 'bank notes' are visible only under UV light.
When two light waves meet, we think it will result in more brightness. But sometimes, the two light wave cancel each other and gives us darkness. (can be shown only in a lab).
There is also bright side to darkness. Without darkness, we can not explore sky and cosmos; we cannot sleep peacefully; we cannot enjoy a movie; we cannot study and under stand the light; we cannot take a photo-camera means dark room; we cannot enjoy laser show and so on.
All the electronic gadgets are black in colour. Other colours and white will disturb the picture that is displayed.
Black hair bordering a girl's face adds more beauty.
Without dark, brightness is a boredom.
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THE EARTH, A SUPER ORGANISM

JOIN MY COURSE: "Become a programmer in a day with python" A man called 'love lock' (what a name) proposed a theory called Gaia theory, named after Greek Goddess. It says, "Earth is a self-regulating organism like a human being. The organic life in it interacts with in-organic matter and maintains atmosphere, temperature and environment". Hence the earth is still suitable for the life to thrive. Imagine, in a particular place, there are lot of flowers. Some flowers are white and some are darkly coloured. We know, white reflects light and heat while dark absorbs the same. White flowers can thrive in hot climate. But dark flowers requires cold climate. The absorption and reflection balances and the environment reaches average, warm temperature at which both the flowers can co-exist. This is the essence of "Gaia" theory. On our earth, the oxygen constitute 20% of the atmosphere. The oxygen level is always mai

THE PARABOLA

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

DISORDER IS THE "ORDER OF THE DAY"

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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