ETERNAL WHEEL OF MOTION

Visible light, X-rays , sunlight, radio waves, television waves, wifi signals, blue tooth signals, cell phone transmission and GPS. All are purely electromagnetic waves made up of electric and magnetic fields. We just want to know how they are created and propagated.

Imagine a positive and negative charges separated by a distance. An invisible line of electric force connects both of them. If we oscillate one of the charges, line of force oscillates and creates a wave like form. ( If you oscillate a rope tide at one end, a wave ripples through the rope)

That is, electric field oscillates or changes with time. According to Maxwell's fourth law, a changing electric field produces changing magnetic field perpendicular to it and encircling it. So a magnetic field wave is produced.

Again Maxwell's third law says, "changing magnetic field produces circulating electric field".

So the result is : The oscillating charges produce changing electric field; changing electric field creates changing magnetic field; then changing magnetic field .... so on and on.

Hence electromagnetic field is created and propagates through empty space by itself. Maxwell proved the existence of electromagnetic wave and he also proved that they travel with the velocity of light using purely mathematics (without doing any experiment).

A star light travels number of years in space before reaching our eyes. This kind of self sustaining motion is possible because of Maxwell's electromagnetic phenomenon.

Comments

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

sciencecapsules

Search This Blog