WHY YOU CANNOT SLOW DOWN THE LIGHT

If you drop an object through the window of the fast moving train, it will follow a curved path and hit the ground. Because, the object carries train's speed even outside the train and gradually slows down. If you fire a gun from fast moving vehicle, you have to add vehicle speed to the bullet's speed.

Suppose, an express train's head light is switched on. The light coming from the lamp travels with its own speed, that is the speed of light. You need not add the train's speed however fast the train may be.

Light is an electromagnetic wave. Here "changing electric field is created by the changing magnetic field and vice versa". Using this mechanism only, light wave progresses. Hence the light wave propagation is independent of its source's motion.

This electromagnetic process cannot be influenced by any other physical phenomenon. So the light wave cannot be sped up (pushed) or slowed down.(pulled)

The formula for the sped of the light is

Here all are constants
Hence the speed of the light is also absolute universal constant.

Unlike other motions, the light ray does not slow down and come to a halt. It travels for ever with fixed velocity. This concept is discovered by maxwell purely using mathematics and it is the corner stone Einstein's theory of relativity.

Note: Suppose light travel through a slab of glass, it will be slowed down by the glass. But once the light enters the air. it gets back the original speed.

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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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