6.Chapter2.Geo.Representation of the Earth

Chapter2

Representation of the Earth.

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With the availability of actual photographs and pictures, it has become clear that the earth is spherical in shape.  In order to study the details about the earth, it is represented in different ways.  The most popular ones are the representations in the form of a globe and a map.  Let us study more about them.  North Pole GLOBE E A globe represents the three-dimensional view of the earth, ft shows the shape of the oceans and the continents correctly.  It also shows their correct relation to one another as they are on the earth.  Like, the distances based on scale and directions of places are fairly correct on the globe.  A globe gives sun's rays us a better idea of ​​parallels (latitudes and meridians fainers South Pole Equator of Earth's SPIN airborne (longitudes), as it is three-dimensional.  . Only a globe gives us an idea about the tilt of the earth's axis) Axis of Earth With - all these advantages, the globe has certain limitations also.  It is difficult to carry the globe around.  Although inflated globes made of plastic are also available, yet, inflating and fixing at the axis takes lot of time.  TOETU Globe cannot be used if we want to study a specific part of the earth.  It does not show details, such as towns, villages, roads and railways, etc.  , of a country.  If we want to study a country, a state or a district, a map is more useful.  MAP A map is a representation of the earth or a part of it, drawn on a flat surface as per the scale.  A map is a two-dimensional representation of the earth.  Although, a map does not give us an idea of ​​the true shape of the earth yet it has some advantages.  Map is useful for showing large areas as well as very small areas.  Very minute details can also be shown on a map, For example, a map can show

Page 14 Several geographic, natural and cultural elements, such as mountains, hills, rivers, distribution of forests, Do You Know?  rainfall, sources of irrigation, location of historical The word 'map' is derived from the places, etc.  A map can be folded, rolled or bound in a Latin word mappo which means a book and carried easily 'napkin' or a cover cloth.  Map - making is an art and requires a special skill and training.  The science of map - making is known as Cartography, and the experts of map - making are called Cartographers.  History of Map - making the earliest map was made in 2300 BC in Mesopotamia (Iraq).  It was made on a clay tablet.  But the maps of that period were not very clear.  They only showed the boundary of the land.  Different techniques of map - making were adopted in different parts of the world.  Eskimos made maps by sewing animal skins of different colors, The Egyptians engraved the boundaries and features on metal plates The ancient maps were based on memory and information.  They were not drawn to a scale.  Thus, they can be called mere sketches, (Ptolemy, an Egyptian, was the first cartographer, who made the map of the world according to scale and direction. He was the first person to represent the earth as a sphere. He was known as  the "Father of map - making? components of maps let us now study the language or the components of the map which help us to read 6Km or interpret a map. The main components are 1: 100,000 scale, direction, symbols and color scheme.  Scale Scale: You know that a map shows a large area on a small sheet of paper. Each map is drawn Do you know? According to a scale, the map scale is the ratio of distance between two points on a map with Mostly scale is  represented in a form of a corresponding distance between the same For example, 1: 500 means 1 cm on the map is Linear Scale or RF (Representative Fraction) points on the ground for example, the distance representing 500 cm of the ground, of  5 km on ground is represented as 1 cm on the  on the map, the scale written on the map shall be 1 cm = 5 km 14

Page 15 Do you know? The Chinese invented the direction 

Direction: It is the second component of the map.  Direction indicates the location and position of the places in relation to each other.  North, South, East and West are the Cardinal Points of the compass.  Other intermediate directions are North - West, South west, South - east and North - east.  The Chinese invented the compass.  If we are in a field or travelling across an ocean, we use a compass to find the directions.  A compass has a magnetic needle which rotates freely on a pivot.  By placing the compass on a plain surface, the needle comes to rest.  It then points towards the north and south direction.  The darker or colored side of the needle at rest, always points towards the North.  Keep the compass away from metallic objects.  It can cause a false reading if kept too close to them.  Symbols: Forests, rivers, hills, railway lines, and roads are shown by some common symbols on a map.  With the help of common symbols, we can read a map made in any country without knowing the languages ​​of that country.  These symbols are known as conventional symbols.  The symbols make the map reading easy and quick.  UURT Color Scheme: Like common symbols, a common color scheme has also been adopted for showing different relief NORTH WEST + EAST 5 $ 35 SOUTH Compass Boundarias International State Roads Metalled Non metalled Bridge Railway Line Broad Gauge Meter Gauge Temple River Mosquo Tank 68 Dam MITTITT  Church Spring + Con là Trà Vilage THE Deciduous Tree Conventional Symbols

 Page 16  features on a map.  Blue color is used for showing water bodies, like oceans, seas, etc.  Low lande and plains are represented by green color.  Higher parts, like plateaus and hills are shown by yellow and orange colors, while brown color is used for showing mountains.  Snow - capped areas are shown by using white color.  This scheme of colors for showing relief features on maps is the same throughout the world) Types of Maps Maps are broadly classified on the basis of scale or the type of information they contain.  On the basis of scale, these are categorized as large scale maps and small scale maps.  • Large scale maps They represent small area on large scale.  Such maps are topographic maps which show greate details of cities, villages, mountains, etc.  They represent these details with the help of contour and symbols.  For example, the scale may be 1 cm = 1 km.  It means one centimetre on a map i representing like one kilometre of the ground.  • Small scale maps Small scale maps are those maps which show larger areas with less details.  Wall maps or atla maps showing world, continents, countries and states with limited information are small scale maps.  For example, the scale may be 1 cm = 100 km, i.e.  One centimetre on the map is representing like 100 kilometres on the ground, Some maps represent a particular theme or a feature.  Some of them are described below.  e political maps they represent the political boundaries of a village, city, state, country and continent.  For example, the map of India showing its states, is a political map.  8 Physical maps Comparison They represent physical or relief features of a place.  They generally show features like mountains, plateaus, plains, rivers, lakes, etc.  ) e Thematic maps A thematic map emphasizes a particular theme or special topic, such as the average distribution of rainfall, distribution of crops, minerals, population, lines of transport, etc.  , in an area.  They are used to enhance one's understanding of the map's theme and purpose.  

PLAN A plan is a layout of a building, a factory, a playground, etc.  It is drawn on a comparatively large scale and shows directions.  The details of rooms, varandahs, open spaces, etc.  , are shown along with their dimensions.  The only difference between a map and a plan is that a map shows important and selected

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features for definite purpose but a plan is a layout of very small area.  With the development of computer technology, the technique of map - making has undergone changes.  A computer helps to draw very accurate, sharp and neat maps.  If you compare an old map with a computer generated improved map, you can easily know the difference between them.  The new maps possess high degree of accuracy ATLAS An atlas is a collection of maps of the world, the continents and selected countries.  It may also include information and diagrams dealing with various topics like the solar systems, geographical features of the earth, population data, etc.  I have INDIA States and Union Territories.  INDIA RABIA SEA ENDAL REFERENCES LEGEND RA IMOLAN INDIAN OCEAN Physical map Political map * Amaravati is the capital of Andhra Pradesh.  Keywords three-dimensional an object that has height, width and depth.  two-dimensional: an object with length and width.