WHEN THE MEASUREMENT GOES OUT OF HAND ....

A severe earthquake is many many times stronger than a shake of the table. How to measure both of them in a scale from 1 to 10? The sound of a bomb blast is many times highly intense than a whisper. How to measure them in a scale of 1 to 100 ?
Here logarithms comes to our help.

we know,
10^2 = 100
log 100 = 2.0000
(base 10)
2.0000 is the logarithm of 100 to the base of 10
similarly,
log 10000000000 = 10.0000
(base 10)

Hence using the idea of logarithm, we can represent any number lying between 100 and 10000 crores in the scale of 2 to 10.
example:
log 102456 = 5.010537
(base 10)
Long range of numbers can be compressed using logarithms.

In the case of earthquake, the formula is,
R = log (A/A0)
A0- the intensity of smallest detectable shock wave by seismograph.
A - the intensity of earthquake wave
If we get R as 3, the earthquake is 1000 times intense than the smallest disturbance. Since log 1000 = 3.0000 This scale is popularly known as Richter scale.

Formula for measuring sound intensity
d = log (P/P0)
P0 - weakest sound human can hear.
P - real intensity of sound.
Here the unit is decibel. D= 50 decibel means the sound is 10000 times stronger than a murmur.

Logarithms is originally invented to make numerical calculations easy. But the advent of electronic calculators and computers made it obsolete. But the logarithmic function is still useful as above.

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THE EARTH, A SUPER ORGANISM

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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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