SPECTACULAR SPECTRUM

When white light is sent through prism, it is split into colors. A great discovery by Newton. Raindrops acts like a prism and split sun light into seven colors forming the rainbow in the sky.

Let us go deeper into this phenomenon.

Take two carbon pencils (rods) both should be sharpened at one end. Connect positive of high voltage to one rod and the negative to another. Place the two pencils face to face so that there is a little gap between the sharpened ends.
Now powerful white spark will appear in the gap. Actually carbon pencils burn. This set up is called 'carbon-arc lamp' used as a light source in old cinema film projector.

If this light is sent through the prism, it split into spectrum of colors. Since the light comes from carbon atoms, the colors can be called carbon spectrum. (see photo). The pattern of colors is unique to carbon. No other element will give out same arrangement of colors. The spectrum is like finger print of the element carbon.

famous double lines of sodium

We can extract spectrum from all the elements in the periodic table. For example, we know sodium lamp, gives out yellow light. If it is sent through the prism, it split into two yellow colors known as sodium doublet. (yellow in two wavelength). So it is the 'ID' of sodium.

Since light and spectrum is the atomic phenomenon, the colors reveal information about atomic structure of the element(arrangement of electron).

Sunlight gives out spectrum called 'solar spectrum' using which we can study the sun's atmosphere. We can find out the elements present there.

It is possible to form spectra from star light. It can yield info.about the star.

If the source of light moves, the position of colors in the spectrum shifts, called Doppler shift. Using Doppler shift, the speed and direction of any moving source of light, (for example a star) can be calculated.

Next time , when you see colors in a rainbow, in a soap bubble, in a water fall, remember they hold so much knowledge.

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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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