UNDERSTANDING ENERGY

Physics says: If a body is moved to some distance by a force, work is said to done. The capacity to do work is energy. In short, the amount of work that can be done gives the measure of energy.

A body at a height can fall down (does work). So it said to posses "potential energy".
A fast moving body can hit another body and do some work. So it has "kinetic energy".

In a chemical battery, oxidation takes place in the negative end and the reduction takes place at the positive end. Hence the electrons are pulled from the negative to positive through a wire and the electric current is established. Here chemical energy turns into "electrical energy".
If the electric current flows through a coil of wire, magnetic field is established. This magnetic field can repel and attract another magnet. So motions will be created. Here electrical energy turns into mechanical energy.

In a chemical reaction, when a molecular bond is broken, energy is utilized. When the atoms form molecule, energy is released. Hence in a chemical reaction the net energy is released. This concept is used in the following energy conversions.
1. Petrol can burn, produce heat, gases expand, pushes the piston of an engine and does some work. Here "chemical energy" turns into the "heat energy".
2. The glucose in the food is converted into energy which fuels muscle contractions. The ATP molecules in our body stores and carries the energy. The heart beats and pumps the blood using the food energy.

Let light photons hit on the materials like zinc, electrons are knocked out from zinc atoms. The ejected electrons can flow through the wire and form current. So even ordinary light carries energy.

Finally, energy means work. Work means particles should be moved to some distance. This fact is true in all the above cases.

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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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