+91-9246365622 Vidyarthi - Bharat Ki Shakti [email protected] APPSC - PRELIMS GEOGRAPHY WORLDGEOGRAPHY www.OnlineIAS.com www.OnlineIAS.com N. Kalyana Chakravarthy 1 +91-9246365622 Vidyarthi - Bharat Ki Shakti [email protected] CONTENTS Sl. No. TOPICS Pg. No. GENERAL GEOGRAPHY 1. Our Universe ...........................................................................................7 2. Interior Infrastructure of Earth ............................................................... 16 3. Mineral & Rocks ......................................................................................21 4. Forces Effecting the Earth Movements ....................................................25 5. Weathering & Erosion. ............................................................................. 27 6. Geogmorphological Landforms ................................................................ 30 7. Volcanoes Earthquakes ............................................................................ 34 8. Erosional and Depositional Landforms................................................... 39 9. Drainage System & Patterns ..................................................................44 10. Atmosphere. .............................................................................................46 11. Climatic Classification...............................................................................58 12. Hydrosphere ............................................................................................60 13. Soil...........................................................................................................69 14. Natural Vegetatiowww.OnlineIAS.comn ..................................................................................73 15. Population ...............................................................................................79 16. Human Settlement.................................................................................. 84 17. Agriculture. ............................................................................................. 89 18. Fisheries ................................................................................................. 100 19. Minerals ................................................................................................ 103 20. Industries.............................................................................................. 108 21. Energy Resources .................................................................................. 117 22. Transport ..............................................................................................122 www.OnlineIAS.com N. Kalyana Chakravarthy 2 +91-9246365622 Vidyarthi - Bharat Ki Shakti [email protected] www.OnlineIAS.com www.OnlineIAS.com N. Kalyana Chakravarthy 3 +91-9246365622 Vidyarthi - Bharat Ki Shakti [email protected] GENERAL GEOGRAPHY www.OnlineIAS.com www.OnlineIAS.com N. Kalyana Chakravarthy 4 +91-9246365622 Vidyarthi - Bharat Ki Shakti [email protected] www.OnlineIAS.com www.OnlineIAS.com N. Kalyana Chakravarthy 5 +91-9246365622 Vidyarthi - Bharat Ki Shakti [email protected] OUR UNIVERSE Origin helium and heat and light is emitted. Thus a star is formed. When the hydrogen of a star is depleted, The big bang theory explains the origin of our its outer regions swell and redden. This stage of a universe. According to this theory, 15 billion years star is called a 'Red Giant'. Our sun will turn into ago, cosmic matter was in a compressed state from a 'Red Giant' in 5 billion years. 'Novae Stars' are which expansion started by a primordial stars whose brightness increases suddenly by 10 to explosion. The super-dense ball broke to form 20 magnitudes due to explosion and then the stars galaxies, which again broke to form stars and again fade into normal brightness. 'Super Novae' finally stars broke to form planets including earth. are stars whose brightness suddenly increases Since the outer space is limitless, conventional by more than 20 magnitudes. After the explosion, units for measuring distances are not suitable. the dense core of comparatively smaller stars is Hence new units as follows are used: called the 'white dwarf'. The dense core of the • Light Year: Distance covered by light in comparatively larger stars is called the one year in vacuum at a speed of 3x108 'Neutron star'. The neutron star rotates at a high m/s. One light year is equal to 9.46 × speed emitting radio waves. Such stars are called 1012 kilometers. 'Pulsar'. 'Black hole' stage of the star occurs when • Astronomical Unit: The Mean distance the ancient star collapses. Gravity becomes so between the Sun and the Earth (1.49 x intense in the hole that nothing escapes, even 8 10 km). One light year is equal to 60,000 light. AU. • Cosmic Year: Sun's period of revolution Constellations around the galactic centre (250 million years). Also called as 'galactic year' In the sky at night there are various patterns • Parsec: Distance at which the mean ra- formed by different groups of stars. These are dius of the Earth's orbit subtends an called constellations. Ursa Major or Big Bear is angle of one second of an arc. It is equal one such constellation. One of the most easily to 3.26 light years. recognizable constellations is the small bear or Saptarishi (Sapta-seven, Rishi-sages). It is a group of seven stars that forms a part of the large Ursa Galaxieswww.OnlineIAS.com Major Constellation. These are huge congregation of stars that hold Solar System together by force of gravity e.g. the Milky Way, Andromeda galaxy, large and small magellanic The sun along with its eight planets, asteroids cloud, Ursa Minor system, sculptor system, etc. and comets comprise the 'solar system'. The planets Milky Way or Akashganga is our home galaxy. are divided into inner or terrestrial planets which Our solar system is located in this galaxy. have higher densities e.g. Mercury, Venus, Earth and Mars and outer planets which have lower Stars densities e.g. Jupiter, Saturn, Uranus and Neptune. Stars are self luminous bodies that account for 98 percent of the matter in a galaxy. In the The Sun universe, some stars appear small but emit more energy than the other stars of the Milky Way. • The sun is in the center of the solar Such stars are called 'Quasars'. When the dense system. galactic nucleus is compressing to form a star, this • It is made up of extremely hot gases par- stage in star formation is called a 'protostar' stage. ticularly hydrogen. Due to high temperature hydrogen converts to • The sun is 109 times bigger than the www.OnlineIAS.com N. Kalyana Chakravarthy 6 +91-9246365622 Vidyarthi - Bharat Ki Shakti [email protected] earth and weighs 2 × 1027 tonnes. 45,000. 'Ceres' whose length is about 1000km is • The sun is about 150 million km away the largest one. They revolve around the sun in from the earth. The light from the sun the same way as the planets. reaches earth in about 8 minutes. • The glowing surface of the sun is called Meteors and Meteorites 'Photosphere'. Above the 'Photosphere' The meteors are the remains of comets which is red coloured 'Chromosphere'. Beyond are scattered in the interplanetary space of the the Chromosphere is the 'Corona', vis- solar system. On contact with the earth's ible during eclipses. atmosphere, they burn due to friction. Those • The temperature of the photosphere is which completely burn out into ash are called about 6000°C and that of the Chromo- meteors or 'shooting star.' Those which do not sphere is about 32400°C, and that of the burn completely and strike the earth in the form corona about 2,700,000°C. The core of of rocks are called 'meteorites'. the sun has a temperature about 15 million degrees Kelvin. But that tremen- Planetary System dous heat is not felt so much by us be- cause despite being our nearest star, it is There are eight planets in our solar system. far away from us. They are: Mercury, Venus, Earth, Mars, Jupiter, • It takes 250 million years to complete Saturn, Uranus and Neptune. Earlier, Pluto was one revolution round its centre. This considered as a planet. But recently it has lost this period is called 'Cosmic year'. status. All the eight planets of the solar system • Sun spots' are dark patches notched on move around the sun in fixed paths. These paths the surface of the sun. They appear dark are elongated. They are called orbits. A new planet because they are cooler i.e. they have a 2003 UB 313 has been discovered recently in our temperature of about 1500°C. solar system. It is bigger than Pluto and farthest • The 'Aurora Borealis' or northern lights from the Sun. are multicoloured lights that sweep across the sky in waves and are visible A. Mercury in the arctic region. The 'Aurora Aus- 1. Mercury is the smallest and the nearest tralis' or southern lights are similarly planet to the Sun. visible near the Antarctica region. 2. It takes only about 88 days to complete The Moon one round along its orbit. • The moon is the only satellite of the earth. 3. It has no atmosphere and no satellite. • Its size is approximately one-fourth that 4. Its days are scorching hot and nights are of the earth. It has a diameter of 3475 frigid. km. • Its orbit is elliptical. The maximum dis- B. Venus tance (apogee) of the moon from the earth is 406,000 www.OnlineIAS.com km and the minimum 1. Venus is considered as 'Earth's-twin' distance (perigee) is 364,000 km. because its size and shape are very much similar to that of the earth. • The moon moves around the earth