S CREATIVE WRITER

Metals and Non-metals Elements can be grouped into two broad categories-metals and non-metals. Metals are elements that are Opaque, lustrous, and good conductors of heat and electricity. lron, gold, and silver are common metals. Non-metals are elements that cannot conduct electricity or heat very well. Examples of non-metals are oxygen, hydrogen, and carbon. Only 18 elements in the periodic table are generally considered non-metals while there are over 80 metals. Properties of metals ° Metals have lustre. They are shiny when cut, scratched, or polished. ° They are malleable, that is, they can be hammered into thin sheets without breaking. ° They are good conductors of electricity and heat. ° They are ductile, that is, they can be melted and drawn into thin wires. ° All metals except mercury are solid at room temperature. ° Most metals have high melting points. Properties of non-metals ° Non-metals have no lustre, that is, they have a dull appearance. ° Th

Aside from unsuccessful attempts at invasion in 1274 and 1281 by the Mongols under Emperor Kublai Khan, Japan has neither faced a foreign invasion nor a crisis of national sovereignty due to foreign invaders throughout its history. A nine hundred-ship fleet faced a fierce challenge from Japanese samurai and bad weather; and was forced into retreat in 1274, the first attempt at invasion. In this attempt, a combined force of about thirty thousand Mongols, Chinese and Koreans tried to subdue Japan but were driven back by a big typhoon. Prior to this invasion, the Mongol leader Kublai Khan, who had succeeded in subduing most of China and Korea, sent emissaries and demanded that Japanese rulers accept their country as being a tributary vassal of the Mongol kingdom. This was rejected by the Regent Hojo Tokimune (125 l~84) in Kyoto. After failing in his first attempt, Kublai Khan became even more determined to invade the Japanese archipelago. He sent a mission of envoys to convince the Jap

Origin of the Japanese The origin of the Japanese people is still obscure. mysterious, and dispute” by anthropologists, historians, and scientists. but many people believe that they are the products of mixed ancestry of immigrants from central parts of Asia the southern region of China. Southeast Asia and the South Pacific islands: Observing their physical traits. biological characteristics, and a Mongoloiq resemblance, and the geographical location of Japan, it is not very difficult tr} come to a conclusion that the dominant group of migrants had entered from mainland Asia via the Korean peninsula; although other races like the Ainu were believed to be living in the Japanese archipelago before the arrival or modern Japanese. Modern Japanese might be the descendants from a fusion of several races of migrants. The people who came from mainland Asia, mainly by the way of the Korean Peninsula, might have played the dominant role. Among these, the Manchu-Koreans, Chinese, or Mongol

Studying Science The curiosity of humans to know more about the natural world has been observed throughout history. Humans have recorded their observations since time immemorial. These observations formed the basis of early scientific records. Modern science emerged in 16th and 17th century during the Renaissance in Europe. Before the Renaissance, almost all people believed whatever was told to them by the government and whatever was written in the religious scriptures  without any question. The Renaissance gave birth to the questioning mind of the human being. It saw a more methodical and scientific approach to knowledge. The works of Galileo and Francis Bacon led to the emergence of modern science. Biology The word ‘biology’ is derived from the Greek Word bios meaning life and logos meaning the study and description of the life of animals and plants. Hippocrates and Aristotle were the first people to study life in a systematic and scientific manner. Father of Medici

Computer The computer is one of the most amazing inventions of man of this let century. In, this world, computer plays the vital role. It has covered almost all parts of human life. The credit of the invention of computer goes to Charges Babbage. So, he 18 called as the father of computer. Computér is an electronic device which receives input data, process them and gives meaningful output as r a result. It even stores a lot of mformation which can be u processed and analyzed through computer for many purposes. On the basis of size, computers are categorized into four classes,they are super computer, mainframe computer, mini computer, microcomputer. Computer is used widely because of its speed, accuracy and precision. It is used in industries for calculating income, expenditure and value of products Complicated calculations can be carried out accurately in a few seconds. It can process information very fast and more accurately.So it is widely used in schools, banks, railways,

Global warming is the gradual warming of the Earth’s atmosphere. it has resulted In an Increase in the sea level. It has also led to changes in climatic conditions all over the world. Warming and cooling of the Earth’s atmosphere has been a natural phenomenon. It has occurred over the ages but the warming of the atmosphere in the last few decades had been faster than before. The atmospheric temperatures have gone up by three times the average for the 20th century since 1970. Global warming has been attributed to the increased emission at greenhouse gases. The increase in the amount of greenhouse gases has made Earth warmer than usual. It is also causing great problems tor the survival of planet Earth. Greenhouse gases Gases that contribute to global warming are known as greenhouse gases. Water vapour is the most abundant greenhouse gas, followed by carbon dioxide (CO), methane (CH 4), nitrous oxide (N20), halogenated fluorocarbons (HCFCs), ozone (O3), perfluorinated ca

Bicycle Bicycles are vehicles with two wheels, a handlebar, and a seat. They do not have an engine and are propelled by foot pedals. They are the principal mode of transportation in many countries. Cycling is also a popular form of sport and leisure activity. Bicycles vary in shape, size, and use. They are used by people for many different purposes including recreation, exercise, and transportation. They are common throughout the world and especially in Chino, lndia,Brazil,ltoly, South Korea, Japan, Taiwan, and the United States. Cycling is also an Olympic sport. Early attempts Many attempts were made to invent the bicycle. The bicycle was not invented by one single person. In 1490, Leonardo Da Vinci made the first known drawing of a bicycle. Jean Teson invented a bicycle like vehicle in 1645 in France. It resembled a bicycle but was a four-wheeled machine. It had no brakes, pedals, or steering mechanism and needed foot movement. Celerifere Comte Mede de Sivrac, a F

Microwaves Microwaves are electromagnetic radiations. They are used for generating heat and are also used for communications. Longer microwaves like those used in a microwave oven are used to cook food. Shorter microwaves are used in communication and weather forecasts. Microwaves, which are used for radars, are just a few centimetres long. Short and long microwaves Each wave has a certain shape and length .The distance between peaks or high points is called wavelength. Microwaves are of two basic types depending on their wavelengths-short and long microwaves. Short microwaves have short wavelengths that can be measured in centimetres, while the long microwaves have wavelengths of about a foot. Discovery The existence of microwaves was predicted by a Scottish scientist, James Clerk Maxwell, in 1864. His equations predicted the existence of microwaves. Twenty-four years later, in 1888, Heinrich Hertz demonstrated that Maxwell was right about the existence of microwaves.

Solids,Liquids and Gases Matter can exist in different states. Solids, liquids, and gases are three common states of matter. Solids have fixed shape and volume. Rocks and woods are solids. Liquids have indefinite shape, usually determined by the containers they till. Water and milk are examples of liquids. Gases have no shape. Examples of gases are oxygen and nitrogen gas. Solids Solid is the densest state of matter. Solids can be made of elements or compounds They can also be made of mixtures, or combinations of diiferent elements and compounds. Most rocks are mixtures of many elements and compounds. The molecules of solids are very tightly bound and packed into regular shapes. There is a very little free space between the molecules and they cannot move.This gives solids their fixed shape and volume. Liquids Liquids are less dense than solids. The molecules of a liquid are not held together as strongly as in a solid. They can move around each other. This enables t

Electricity Electricity is a form of energy. it is the movement of electrons or protons in a material. Electrons are negatively charged atomic particles, while protons are positively charged. Electrons in a conductor move from a negatively charged point to a positively charged point. Electricity is present everywhere in the world. Lightning is  Form of electricity produced by clouds. Even the human body contains weak electric signals that low in the nerve cells. Electricity can be changed into other forms of energy, such as  heat and light. it is used to produce light, heat, power, etc. Electric current Electric current is the flowing of charge through a wire. Charge can flow only through a conductor. Therefore, electricity can flow only through a conductor. There are two types of electric current-direct current and alternating current. Direct current flows only in one direction while alternating current reverses its direction at regular intervals. Electric circuit Elec

Grand Canyon The Grand Canyon is one of the natural wonders of the world. It is a deep, wide gorge carved by the Colorado River in northern Arizona, United States. It is one of the most beautiful canyons of the world. Colorado plateau The Colorado Plateau is a large beautiful plateau in south-western United States. It  is characterised by horizontal, layered rocks, lava flows, deep canyons, barren, and dry lands. The climate is dry and arid and the area is. sparsely vegetated. The plateau covers an area of around 3,32,850 sq km and has an average elevation of 1,500 m. It includes areas drained by the Colorado River and its territories. The Grand Canyon section of thegplateau is the highest section of the Colorado Plateau. The Grand Canyon lies In the south-western portion of the Colorado Plateau. The mighty Colorado River has cut through the rocks of the Colorado Plateau lot about 6 million years forming the canyon. The canyon is 43.2 km long, 6.4 to 28.8 km wide, and is