The Earth takes a year to orbit the sun. it is about 365 days. The exact time is 365.242199 days. To make years come out even, every four years there is a leap year. It has 366 days. The months on the calender are based on the phases of the moon. The Greeks has a 10 month calender. About 60 days were left over. So the Romans added two months. The idea of seven day weeks come from the HOLY BIBLE. The Romans named the days. We still use three of these names: Sunday ( Sun day), Monday (Moon day) ans Saturday ( Saturn day).
Thursday, 6 February 2014
Tuesday, 4 February 2014
JACK FRUIT GREW IN MY BEAUTIFUL VILLAGE CHETTIKULAM
This post views the tasty sweet fruit grew in our beautiful village CHETTIKULAM .The name of this fruit is JACK FRUIT , in Malayalam we call it as "CHAKKA" Its really a tasty fruit. Even the kids to old age people like this fruit. When this fruit gets ripen even the birds and squirrel came to eat it. It is also used to make curry. Its really a tasty fruit.
Monday, 3 February 2014
FOSSILS
THE FOSSILS ARE THE REMAINS of plants and animals that have been preserved in rock. A fossil may be the preserved remains of an organism itself, an impression of it in rock , or preserved traces (known as trace fossils) left by an organism while it was alive, such as organic carbon outlines, fossilized footprints or droppings. Most dead organisms soon rot away or are eaten by scavengers. For fossilization to occur, rapid burial by sediment is necessary. The organism decays, but the harder parts-bones,teeth and shells foe example-may be preserved and hardened by minerals from the surrounding sediment. Fossilization may also occur even when the hard parts of an organism are dissolved away to leave am impression called a mould. The mould is filled by minerals, there by creating a cast of the organism. The study of fossils (palaeontology) can not only show how living things have evolved, but can also help to reveal the Earth,s geological history-for example , by aiding in the dating of rock strata.
GALAXIES
A GALAXY IS A HUGE MASS OF STARS, nebulae, and interstellar material. The smallest galaxies contain about 100,000 stars, while the largest contain up to 3,000 billion stars. There are three main types of galaxy, classified according to their shape: elliptical, which are oval shaped; spiral, which have arms spiraling outwards from a central bulge; and irregular, which have no obvious shape. Sometimes, the shape of a galaxy is distorted by a collision with another galaxy. Quasars (quasi-stellar objects) are thought to be galactic nuclei but are so far away that their exact nature is still uncertain . They are compact, highly luminous objects in the outer reaches of the known Universe; while the furthest known "ordinary" galaxies are about 10 billion light years away, the furthest known quasar is about 15 billion light years away. Active galaxies, such as Seyfert galaxies and radio galaxies, emit intense radiation. In a Seyfert galaxy, this radiation comes from the galactic nucleus; in the ratio galaxy, it also comes from huge lobes on either side of the galaxy. The radiation from active galaxies and quasars is thought to be caused by black holes
Sunday, 2 February 2014
THE MILKY WAY
THE MILKY WAY IS THE NAME GIVEN TO THE FAINT BAND OF LIGHT that stretches across the night sky. This light comes from the stars and nebulae in our galaxy, known as the MILKY WAY Galaxy as "the galaxy". The galaxy is shaped like a spiral, with a dense central bulge that is encircled by four arms spiralling outwards and surrounded by a less dense halo. We can not see the spiral shape because the solar system is in one of the spiral arms, the orion arm ( also called the Local arm ). From our position, the center of galaxy is completely obscured by dust clouds; as a result, optical maps give only a limited view of galaxy . However, a more complete picture be obtained by studying radio, infra-red and other radiations. the central bulge of the galaxy is a relatively small, dense sphere that contains mainly older red and yellow stars. The halo is a less dense region in which the oldest stars are situated; some of these stars may be old as the Galaxy itself ( possibly 15 billion years). The spiral arm contains mainly hot, young, blue stars as well as nebulae (clouds of dust and gas inside which stars are born). The Galaxy is vast, about 100,000 light year across ( a light year is about 9,460 billion km); in comparison, the solar systems seems small st about 12 light hours across ( about 13 billion km). the entire Galaxy is rotating in space, although the inner stars travel faster than those further out. The sun, which is about two-thirds out from the center, completes one lap of the Galaxy about every 220 million years.
Saturday, 1 February 2014
ENERGY
ANYTHING THAT HAPPENS- from a pin drop to an explosion-requires energy. Energy is the capacity for "doing work" (making something happen). Various forms of energy exists including light, heat, sound, electrical, chemical, nuclear, kinetic and potential energies. The law of conservation of energy states that the total amount of energy in the universe is fixed- energy cannot be created or destroyed. In means the energy can only change from one form to another ( energy transfer). For example, potential energy is the energy that "stored" , and can be used in the future. An object gains potential energy when it is lifted; as the objected is released, potential energy changes into the energy of motion (kinetic energy). during transference, some of the energy converted into heat. A combined heat and power station can put some of the otherwise "waste" heat to useful effects in local schools and housing. Most of the Earth's energy is provided by the sun, in the form of electromagnetic radiation. Some of this energy transfers to plant and animal life, and ultimately to fossil fuels, where it is stored in chemical form. Our bodies obtain energy from food we eat, while energy needed for other tasks also, such as heating and transport, can be obtained by burning fossil fuels-or by harnessing natural forces like wind or moving water- to generate electricity. Another source is nuclear power, where energy is released by reactions in the nucleus of an atom. All energy is measured by the international unit, the joule ( J ) . As a guide, one joule is about equal to the amount of energy needed to lift an apple one metre.
ELeCtRiCitY AnD MagNETisM
ELECTRICAL EFFECTS result from an imbalance of electrical charge, There are two types of electrical charge ,named positive (carried by protons) and negative (carried by electrons). If charges are opposite (unlike), they attract one another, while like charges repel. Forces of attraction and repulsion (electrostatic forces) exist between any two charges particles. Matter is normally uncharged, but if electrons are gained, an object will gain an overall negative charge; if they are removed, it becomes positive. Objects with an over all negative or positive charge are said to have an imbalance of charge, and exerts the same forces as individual negative and positive charges. On this larger scale, the forces will always act to regain the balance of charge. This causes static electricity. For example, lightning is produced by clouds discharging a huge excess of negative electrons. If charges are "free"-in a wire or material that allows electrons to pass through it - the forces cause a flow of charge called an electric current. Some substances exhibit the strange phenomenon of magnetism-which also produces attractive and repulsive forces. Magnetic substances consist of small regions called domains. Normally unmagnetized, they can be magnetized by being placed in magnetic field. Magnetism and electricity are inextricably linked, a fact put to use in motors and generators.
RESISTANCE: For a given voltage, the flow of current depends upon the resistance of a circuit. Resistance is the degree to which a substance resists electrical current. It is measured in ohms.
Electric motor: In a motor, magnetic forces between the winding and permanent produced a rotatory motion.
Electric generator: In a generator, the rotor rotates within the magnetic field of the stator to produce an electric current.
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