Monday, November 7, 2011

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Miss Venezuela Ivian Sarcos crowned Miss World 2011


Miss Venezuela Ivian Sarcos was on November 06 evening crowned Miss World 2011, and India’s hopes of winning the title for the sixth time came crashing down as Miss India World Kanishtha Dhankhar failed to make it to the top 25.
At an extravagant ceremony at the Earls Court in London, 21-year-old Sarcos defeated over 100 beauties from various parts of the world at the 61st Miss World contest.
Miss Philippines Gwendoline Ruais was the first runner-up and Miss Puerto Rico Amanda Perez became the second runner-up.
The gala event kicked off on Sunday evening with a dynamic performance by British street dance troupe Diversity, followed by the introduction of the Miss World contestants.
It ended with Miss World 2010 Alexandria Mills crowning Sarcos. The jury included former Miss World winners — Cindy Breakspeare (1976), Nigeria Agbani Darego (2001), Zhang Zilin (2007) and Kaiane Aldorino (2009).

Titleholders:
Year Country/Territory Miss World Location Date





2011        Venezuela Ivian Sarcos London, United Kingdom 6 November
2010  USA Alexandria Mills Sanya, China 30 October
2009  Gibraltar Kaiane Aldorino Johannesburg, South Africa 12 December
2008  Russia Ksenia Sukhinova Johannesburg, South Africa 13 December
2007  China Zhang Zilin Sanya, China 1 December
2006  Czech Republic Taťána Kuchařová Warsaw, Poland 30 September
2005  Iceland Unnur Birna Vilhjálmsdóttir Sanya, China 10 December
2004  Peru María Julia Mantilla Sanya, China 4 December
2003  Ireland Rosanna Davison Sanya, China 6 December
2002  Turkey Azra Akın London, United Kingdom 7 December
2001  Nigeria Agbani Darego Sun City, South Africa 16 November
2000  India Priyanka Chopra London, United Kingdom 30 November


BY NUMBER OF WINS:

Country/Territory Titles Winning years
 Venezuela
6
1955, 1981, 1984, 1991, 1995, 2011
 India
5
1966, 1994, 1997, 1999, 2000,
 United Kingdom 1961, 1964, 1965, 1974(resigned) , 1983
 United States
3
1973, 1990, 2010
 Iceland 1985, 1988, 2005
 Jamaica 1963, 1976, 1993
 Sweden 1951, 1952, 1977
 Russia
2
1992, 2008
 Peru 1967, 2004
 Austria 1969, 1987
 Germany 1956, 1980 (resigned)
 Argentina 1960, 1978
 South Africa 1958, 1974 (took over title in November 1974)
 Australia 1968, 1972
 Netherlands 1959, 1962
 Gibraltar
1
2009
 China 2007
 Czech Republic 2006
 Ireland 2003
 Turkey 2002
 Nigeria 2001
 Israel 1998
 Greece 1996
 Poland 1989
 Trinidad & Tobago 1986
 Dominican Republic 1982
 Guam 1980 (took over title on 28 November 1980)
 Bermuda 1979
 Puerto Rico 1975
 Brazil 1971
 Grenada 1970
 Finland 1957
 Egypt 1954
 France 1953

Saturday, November 5, 2011

APPSC 2011 GROUP-2 KEY

                                                           

Friday, November 4, 2011

CURRENT AFFAIRS MCQs

1.  Which among the following constitutional amendment bill contains the provision of increase in women  reservation in panchayats?
a. 110th
b. 111th
c. 112th
d. 113th

2. Who among the following Lokayukta has asked President to censure Chief Minister of Delhi?
a. Santosh Hegde
b. Manmohan Sarin
c. Alok Vadhwa
d. Purshottam Jaiswal
 ‘
3. Which state has announced the decision to demerge its National Institute of Sports (NIS), from the Sports Authority of India (SAI)?
a. Punjab
b. Himachal Pradesh
c. Gujarat
d. Maharashtra

4. What is the name of the New Intelligence Chief, who handed over command of US and NATOled troops in Afghanistan?
a. General David Petraeus
b. General Rodrigue
c. General Basil Peterson
d. General Farimon Luasa

5. Who among the following has recently taken over as the director of the Film and Television Institute of India (FTII)?
a. J P Sinha
b. Sharmila Tagore
c. Shabana Azmi
d. Dharmendra Jai Narain

6. The GSAT-12 communication satellite has been launched successfully on July 15, 2011 by which of the following launch vehicle?
a. GSLV G-6
b. GSLV-F7
c. PSLV C-16
d. PSLV C-17

7. Recently the Defense Research and Development Organization (DRDO) successfully flighttested its latest missile Prahaar from the Launch Complex III of the Integrated Test Range (ITR) off the Chandipur coast in Balasore district. Prahaar is a
a. Surface to surface missile
b. Surface to air missile
c. Air to surface missile
d. Sea to air missile

8. Chinese and Southeast Asian officials have agreed on a draft of guidelines to avert tension in the South China Sea at a meeting held with senior officials of the 10-member Association of Southeast Asian Nations, or ASEAN at:
a. Manila (Philippines)
b. Bandar Seri Begawan  (Brunei)
c. Ho Chi Minh city  (Vietnam)
d. Bali (Indonesia)

9. Who is the current Prime Minister of Egypt?
a. Essam Sharaf
b. Gouda Abdel Khalek
c. Mahmoud Eissa
d. Hazem El-Beblawi

10 Hurricane Dora was active recently over the region of
a. Australia
b. Europe
c. South America
d. North America

11. The Cabinet approved the proposal for enhancing reservation for women in Panchayats from the present 33 per cent to 50 per cent with the provision being applicable to all seats filled through
a. Direct election
b. Indirect election
c. Nomination
d. Both direct election and  nomination

12. India signed a civil nuclear cooperation agreement with which of the following country paving the way for the possibility of exporting its atomic power plants recently?
a. North Korea
b. South Kora
c. China
d. Singapore

13. Recently  English  has been dropped as final year subject  in which of the following state university?
a. Mumbai
b. Saurashtra
c. Odisha
d. Himachal Pradesh

14. Which  IIM  has announced extension of  the reach of its publisher training programme to countries in South East Asia from next year?
a. IIM Lucknow
b. IIM Ahmedabad
c. IIM Kozhikode
d. IIM Bangalore

15. What is the name of the Metropolitan Police Commissioner  who resigned following criticism for hiring former News of the World executive Neil Wallis - who was questioned by police investigating hacking - as an adviser in UK?
a. Sir Vinfery simpson
b. Sir Maddley Thomson
c. Sir Anerdson Majle
d. Sir Paul Stephenson

16. Who among the following  was offi cially named as the next envoy of India to the United States of America ?
a. Nirupama Roy
b. A N Ahuja
c. R K Sharma
d. J P S hukla

17. Which of the following personality has been appointed by West Bengal Chief Minister Mamata Banerji as an advisor to ‘Resurgent Bengal’ scheme?
a. Amartya sen
b. Sam Pitroda
c. Arjun Sengupta
d. Usha Thorat


18. The world’s largest Indian flag weighing 250 kg was unfurled at the ‘Vibrant India Festival’ which began recently in –
a. France
b. China
c. Russia
d. USA

19. Minister for Defense A K Antony recently presented the first  Mercy Ravi Award for Woman of Substance to
a. Kiran Bedi
b. Vandana Shiva
c. Sheila Dikshit
d. Arundhati Roy

20. Which among the following  state has announced that 90 per  cent seats in sports academies will be fi lled by players from the  state?
a. Uttar Pradesh
b. Madhya Pradesh
c. Haryana
d. Punjab

21. Who among the following was elected president of the Mumbai  Cricket Association at its 77th annual general body meeting  recently?
a. Manohar Joshi
b. Vilasrao Deshmukh
c. Gajanan karve
d. Sharad Pawar

22. Which among the following is the oldest commissioned ship of  the Indian Navy, ‘a landing ship tanker, which was given a fond  farewell after 35 years of service  recently?
a. INS Jaladh
b. INS Sharabh
c. INS Shankul
d. INS Padmesh

23. Which state has the highest  rural teledensity of 70.23 ?
a. Karnataka
b. Himachal Pradesh
c. Rajasthan
d. Gujarat

24. Who among the following has  become the world’s No. 1 double  trap shooter as per the International Shooting Sport Federation (ISSF) rankings released?
a. Gagan Narang
b. Sanjeev Rathore
c. Vijay Kumar
d. Ronjan Sodhi

25. Which Indian wildlife research and bio-diversity conservation organization will assist Indonesian authorities to undertake non-invasive genetics research on two critically endangered species — the Javan and the Sumatran rhinos — in Indonesia?   
a. Aaranyak
b. Parivesh
c. Paryavaran
d. Sanrakshak
  
26. Which country is stepping into the Indian Ocean for the first time for mineral exploration?
a. Japan
b. Canada
c. China
d. India

27. Which among the following is the latest European country to act against the burqa after France and Belgium have banned the wearing of burqa in public? 
a. Germany
b. Spain
c. Italy
d. Denmark

28. Which Indian-American who is an expert in international finance law, has been appointed as Senior Advisor in the US State Department's South and Central Asia Bureau to cement ties with the Diaspora groups?
a. Mitul Desai
b. Sanjeev Upadhyay
c. Upendra Bansal
d. Manendra Singh

29. Which airline has become the fi rst airline to use biofuels on regular commercial fl ights in a six-month trial that it estimates will reduce CO2 emissions by up to 1,500 tones during the period?
a. Lufthansa
b. Air India
c. Kingfi sher
d. Airbus

30. Which among the following  Governor Generals of India was  the fi rst occupant of Rashtrapati Bhawan of India?
a. Warren Hastings
b. Lord Irwin
c. Lord Willington
d. Lord Rippon

31. Typhoon Muifa has devastated  which among the following countries eastern coast?
a. Indonesia
b. Japan
c. China
d. Hongkong
ANSWERS:
1.  d  Manchester united
1. a 10th
2. b Manmohan Sarin
3. a Punjab
4. a General David Petraeus
5. d Dharmendra Jai Narain
6. d PSLV C-17
7. a  Surface to surface missile
8. d Bali (Indonesia)
9. a Essam Sharaf
10. d  North America
11. a  Direct election
12. b  South Korea
13. b Saurashtra
14. b IIM, Ahmedabad
15. d  Sir Paul Stephenson
16. a  Nirupama Roy
17. b  Sam Pitroda
18. c  USA
19. c  Sheela Diskshit
20. b  Madhya Pradesh
21. b  Vialsrao Deshmukh
22. b  INS Sharabh
23. b  Himachal Pradesh
24. d  Ronjan Sodhi
25. a  Aranyak
26. c  China
27. c  Italy
28. a  Mitul Desai
29. a  Lufthansa
30. b  Lord Irwin
31. c  China

Women and Men in India 2011

                                                           

Thursday, November 3, 2011

THE CONSTITUENT ASSEMBLY

The Constituent Assembly met for the first time in New Delhi on 9 December, 1946 in the Constitution Hall which is now known as the Central Hall of Parliament House. Decorated elegantly for the occasion, the Chamber wore a new look on that day with a constellation of bright lamps hanging from the high ceilings and also from the brackets on its walls.
Overwhelmed and jubilant as they were, the hon'ble members sat in semi-circular rows facing the Presidential dias. The desks which could be warmed electrically were placed on sloping green-carpeted terraces. Those who adorned the front row were Pandit Jawaharlal Nehru, Maulana Abul Kalam Azad, Sardar Vallabhbhai Patel, Acharya J.B. Kripalani, Dr. Rajendra Prasad, Smt. Sarojini Naidu, Shri Hare-Krushna Mahatab, Pandit Govind Ballabh Pant, Dr. B.R. Ambedkar, Shri Sarat Chandra Bose, Shri C. Rajagopalachari and Shri M. Asaf Ali. Two hundred and seven representatives, including nine women were present.
The inaugural session began at 11 a.m. with the introduction of Dr. Sachchidananda Sinha, the temporary Chairman of the Assembly, by Acharya Kripalani. While welcoming Dr. Sinha and others, Acharyaji said: "As we begin every work with Divine blessings, we request Dr. Sinha to invoke these blessings so that our work may proceed smoothly. Now, I once more, on your behalf, call upon Dr. Sinha to take the Chair."
Occupying the Chair amidst acclamation, Dr. Sinha read out the goodwill messages received from different countries. After the Chairman's inaugural address and the nomination of a Deputy Chairman, the members were formally requested to present their credentials. The First Day's proceedings ended after all the 207 members present submitted their credentials and signed the Register.
Seated in the galleries, some thirty feet above the floor of the Chamber, the representatives of the Press and the visitors witnessed this memorable event. The All India Radio, Delhi broadcast a composite sound picture of the entire proceedings.
SOME FACTS
The Constituent Assembly took almost three years (two years, eleven months and seventeen days to be precise) to complete its historic task of drafting the Constitution for Independent India. During this period, it held eleven sessions covering a total of 165 days. Of these, 114 days were spent on the consideration of the Draft Constitution.
As to its composition, members were chosen by indirect election by the members of the Provincial Legislative Assemblies, according to the scheme recommended by the Cabinet Mission. The arrangement was: (i) 292 members were elected through the Provincial Legislative Assemblies; (ii) 93 members represented the Indian Princely States; and (iii) 4 members represented the Chief Commissioners' Provinces. The total membership of the Assembly thus was to be 389. However, as a result of the partition under the Mountbatten Plan of 3 June, 1947, a separate Constituent Assembly was set up for Pakistan and representatives of some Provinces ceased to be members of the Assembly. As a result, the membership of the Assembly was reduced to 299.
On 13 December, 1946, Pandit Jawaharlal Nehru moved the Objectives Resolution
1.This Constituent Assembly declares its firm and solemn resolve to proclaim India as an Independent Soverign Republic and to draw up for her future governance a Constitution;
2.WHEREIN the territories that now comprise British India, the territories that now form the Indian States, and such other parts fo India as are outside British India and the States as well as such other territories as are willing to be constituted into the Independent Soverign India, shall be a Union of them all; and
3.WHEREIN the said territories, whether with their present boundaries or with such others as may be determined by the Constituent Assembly and thereafter according to the law of the Constitution, shall possess and retain the status of autonomous Units, together with residuary powers and exercise all powers and functions of goverrnment and administration, save and except such powers and functions as are vested in or assigned to the Union, or as are inherent or implied in the Union or resulting therefrom; and
4.WHEREIN all power and authority of the Soverign Independent India, its constituent parts and organs of government, are derived from the people; and
5.WHEREIN shall be guaranteed and secured to all the people of India justice, social economic and political : equality of status, of opportunity, and before the law; freedom of thought, expression, belief, faith, worship, vocation, association and action, subject to law and public morality; and
6.WHEREIN adequate safeguards shall be provided for minorities, backward and tribal areas, and depressed and other backward classes; and
7.WHEREBY shall be maintained the integrity of the territory of the Republic and its soverign rights on land, sea, and air according to justice and the law of civilized nations; and
8.this ancient land attains its righful and honoured placed in the world and make its full and willing contribution to the promotion of world peace and the welfare of mankind.
This Resolution was unanimously adopted by the Constituent Assembly on 22 January 1947.
Late in the evening of 14 August, 1947 the Assembly met in the Constitution Hall and at the stroke of midnight, took over as the Legislative Assembly of an Independent India.
On 29 August, 1947, the Constituent Assembly set up a Drafting Committee under the Chairmanship of Dr. B.R. Ambedkar to prepare a Draft Constitution for India. While deliberating upon the draft Constitution, the Assembly moved, discussed and disposed of as many as 2,473 amendments out of a total of 7,635 tabled.
The Constitution of India was adopted on 26 November, 1949 and the hon'ble members appended their signatures to it on 24 January, 1950. In all, 284 members actually signed the Constitution. On that day when the Constitution was being signed, it was drizzling outside and it was interpreted as a sign of a good omen.
The Constitution of India came into force on 2 6 January, 1950. On that day, the Assembly ceased to exist, transforming itself into the Provisional Parliament of India until a new Parliament was constituted in1952
Sessions of the Constituent Assembly
First Session: 9-23 December, 1946
Second Session: 20-25 January, 1947
Third Session: 28 April - 2 May, 1947
Fourth Session: 14-31 July, 1947
Fifth Session: 14-30 August, 1947
Sixth Session: 27 January, 1948
Seventh Session: 4 November,1948 - 8 January, 1949
Eighth Session: 16 May - 16 June, 1949
Ninth Session: 30 July - 18 September, 1949
Tenth Session: 6-17 October, 1949
Eleventh Session: 14-26 November, 1949
[The Assembly met once again on 24 January, 1950, when the members appended their signatures to the Constitution of India]
IMPORTANT COMMITTEES OF THE CONSTITUENT ASSEMBLY AND THEIR CHAIRMEN
Name of the Committee

Chairman
Committee on the Rules of Procedure Rajendra Prasad
Steering Committee Rajendra Prasad
Finance and Staff Committee Rajendra Prasad
Credential Committee Alladi Krishnaswami Ayyar
House Committee B. Pattabhi Sitaramayya
Order of Business Committee K.M. Munsi
Ad hoc Committee on the National Flag Rajendra Prasad
Committee on the Functions of the Constituent Assembly G.V. Mavalankar
States Committee Jawaharlal Nehru
Advisory Committee on Fundamental Rights, Minorities and Tribal and Excluded Areas Vallabhbhai Patel
Minorities Sub-Committee H.C. Mookherjee
Fundamental Rights Sub-Committee J.B. Kripalani
North-East Frontier Tribal Areas and Assam Exluded & Partially Excluded Areas Sub-Committee Gopinath Bardoloi
Excluded and Partially Excluded Areas (Other than those in Assam) Sub-Committee A.V. Thakkar
Union Powers Committee Jawaharlal Nehru
Union Constitution Committee Jawaharlal Nehru
Drafting Committee B.R. Ambedkar
STATEWISE MEMBERSHIP OF THE CONSTITUENT ASSEMBLY OF INDIA AS ON 31 DECEMBER, 1947
PROVINCES-229
S.No

State No. of Members
1. Madras 49
2. Bombay 21
3. West Bengal 19
4. United Provinces 55
5. East Punjab 12
6. Bihar 36
7. C.P. and Berar 17
8. Assam 8
9. Orissa 9
10. Delhi 1
11. Ajmer-Merwara 1
12. Coorg 1
INDIAN STATES-70
1. Alwar 1
2. Baroda 3
3. Bhopal 1
4. Bikaner 1
5. Cochin 1
6. Gwalior 4
7. Indore 1
8. Jaipur 3
9. Jodhpur 2
10. Kolhapur 1
11. Kotah 1
12. Mayurbhanj 1
13. Mysore 7
14. Patiala 2
15. Rewa 2
16. Travancore 6
17. Udaipur 2
18. Sikkim and Cooch Behar Group 1
19. Tripura, Manipur and Khasi States Group 1
20. U.P. States Group 1
21. Eastern Rajputana States Group 3
22. Central India States Group (including Bundelkhand and Malwa) 3
23. Western India States Group 4
24. Gujarat States Group 2
25. Deccan and Madras States Group 2
26. Punjab States Group I 3
27. Eastern States Group I 4
28. Eastern States Group II 3
29 Residuary States Group 4

Total

299

Universe and Solar System

In the vastness of the Universe, the Earth, the Sun and planets are tiny dots. The Sun is a single star in a Galaxy comprising 100,000 million stars.

The Solar System is centred on the Sun. It consists of a star called the Sun and all the objects that travel around it. The Solar System includes : 9 planets (Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto), along with the numerous satellites that travel around most of them; planet-like objects called asteroids (hundreds of asteroids); chunks of iron and stone called meteoroids; bodies of dust and foreign gases called comets (thousands of comets); and drifting particles called interplanetary dust and electrically charged gas called plasma that together make up the interplanetary medium.

The whole solar system by volume appears to be an empty void. This vacuum of ‘space’ comprises the interplanetary medium. The speed of the solar wind is about 400 kilometer per second in the vicinity of Earths' orbit.

The Solar System originated in a primitive solar nebula–a rotating disc of gas and dust. It is from this rotating disc that the planets and the rest of the Solar System evolved. The Solar System is also tucked away in a corner of the Milky Way at a distance of about 30,000 to 33,000 light years from the centre of the galaxy.

The Sun contains 99.85% of all the matter in the Solar System. The planets which condensed out of the same disk of material that formed the Sun, contains only 0.135% of the mass of the Solar System.

Jupiter contains more them twice the matter of all the other planets combined. Satellites of the planets, comets, asteroids, meteoroids, and the interplanetary medium constitute the remaining 0.015%.

THE PLANETS
The bodies revolving around the sun (at the same time rotating on their imaginary axis) are called planets. They have no light of their own but shine by radiating the fight they receive from the sun. They all revolve around the sun in elliptical orbits. Until about 200 years ago only six planets were known. Three more planets were discovered later, the latest being Pluto (discovered in 1930). Nine planets can now be identified.

Mercury
Mercury is the planet nearest to the sun. It rotates on its own axis in 56.65 earth days. It takes 88 days to complete one revolution round the sun. Thus it is the fastest planet in our solar system.

Venus
Also known as the evening star and morning star, is the brightest object in the sky after the sun and the moon. It is slightly smaller than the earth and is the planet closest to the earth. It is also the hottest planet in our solar system and has a weak magnetic belt.

Mars
Mars is the fourth planet from the sun and is the next planet after the earth. Being favorably situated, it is brighter than most of the stars and, is therefore, known as the Red Planet. It has two small satellites called Phobos (Fear) and Deimos (Terror).

Jupiter
Jupiter is the largest planet in our solar system. It is about eleven times larger than the earth. Its volume is one and half times the volume of all the planets combined together. The most conspicuous aspect about Jupiter is its Great Red Spot. It is also known as the giant planet because of its huge size.

Saturn
Saturn is an outer planet visible to the naked eye. Second in size to Jupiter, it is the least dense of all the planets. The most spectacular feature of Saturn is its system of rings. The ring system is made up of a variety of separate particles which move independently in circular orbits. It has 46 satellites. Titan is its biggest.

Uranus
Uranus is the seventh planet from the sun and is not visible to the naked eye. It was identified as a planet in 1781 by William Herchel. It has completed only two revolutions round the sun since its discovery, and takes about 84 terrestrial years to circle round the sun. It has 27 satellites.

Neptune
Neptune is not visible to the naked eye but can be seen through a small telescope as a greenish star. It is eighth in position from the sun. This planet was discovered by J.G. Galle of Berlin in 1846. Till 1930, it was believed to be the farthest planet from the sun and the outermost in our solar system. It has eight satellites, and Triton and Nereid are the most con­spicuous of them.

Pluto
Pluto is the youngest planet to be discovered in our solar system. It was discovered photographically by C.W. Tombaugh (USA) in 1930. It is the smallest planet in our solar system; slightly smaller than Mercury and visible only through a tele­scope. The duration of its revolution round the sun is the longest and it is, therefore, the slowest planet in our solar system.
 
SATELLITES
Satellite are bodies which revolve around the planets. All planets have one or more satellites, except Mercury and Venus. The moon is the earth's natural satellite. There are approximately 62 satel­lites in our solar system.

In August 1989, the US Space probes Voyager-1 and Voyager-2 revealed six new satellites around Neptune which was earlier believed to have only two satellites.

The Moon
The moon is the earth's natural satellite and is its nearest neighbour in space. It revolves around the earth while rotating on its own axis. Only 59% of its surface is directly visible from the earth. Of all satellites in the solar system, the moon is the largest in proportion to its primary body, that is, the earth. All other satellites have sizes below 1/8 the size of the mother planet. The moon is about 1/4 the size of its mother planet, the earth. It takes about 1.3 seconds for moonlight to reach the earth, whereas sunlight takes about 8 minutes and 16.6 seconds to reach the earth.

The moon takes 27 days 7 hours 43 minutes and 11.47 seconds to complete one revolution of the earth. It rotates on its axis in exactly the same time. Hence, we see only one side of the moon.

THE EARTH
Modern theories on the formation of the Earth and other planets are of course based on the Copernican theory.

The age of the Earth was a matter of speculation till very recent times. It was only about 200 years ago, that scientific enquiries were started by geologists. According to their deductions, based on the study of rocks, the age of the Earth is 4.6 billion years.

Our knowledge of the internal structure of the Earth is derived from studies of earthquakes. The shock waves sent out by an earthquake indicate the physical nature of the regions through which they pass. These studies show that the centre of the Earth is a solid core–the Inner Core. The density of this core is about 13 g to the cubic centimeter. The Inner Core is about 1,370 km thick and is surrounded by an Outer Core of around 2,080 km. The Outer Core appears to be molten.

The Outer Core is surrounded by the Mantle which has a thickness of around 2,900 km. The Mantle is topped by the crust of the Earth, which varies widely in thickness–from 12 to 60 km. At the centre or the Inner Core, that is at a depth of some 6,370 km, temperature goes upto some 4,000°C and pressure reaches nearly 4 million at mospheres.

The mantle is important in many ways. It accounts for nearly half the radius of the Earth (2,900 km), 83% of its volume and 67% of its mass. The dynamic processes which determine the movements of the crust plates are powered by the mantle.

Starting at an average depth of from 45 to 56 km below the top surface of the Earth, the mantle continues to a depth of 2,900 km where it joins the outer core. The mantle is a shell of red hot rock and separates the Earth's metallic and partly melted core (both the inner and the outer cores) from the cooler rocks of the Earth's crust.

It is composed of sllicate minerals rich in magnesium and Iron. The density of the mantle in­creases with depth from about 3.5 gram per cubic centimetre to around 5.5 gram, near the outer core.

The outer surface of the Earth is divided into 4 spheres:
Lithosphere means the entire top crust of the Earth and includes not only the land surface but also the ocean floor.
Hydrosphere is the water sur­face which includes the oceans, lakes and rivers.
Atmosphere is the blanket of air that envelops the Earth. It covers both the land surface and the water surface.
Biosphere is this sphere of life which spreads over all the three other spheres.

Earth's Movements
The earth has two types of move­ments, viz. rotation or daily motion and revolution or annual motion.
The earth spins on its own im­aginary axis from west to east once in 24 h (in precisely 23 h 56 min and 40.91 s). It is also called diurnal or daily motion. The axis is an imaginary line which runs form north to south and passes through the centre of the earth. It always remains in­clined at an angle of 66½° to the plane of the earth's orbit.

Effects of Rotation:
(i) Occurrence of day and night.
(ii) The position of a place on earth can be fixed.
(iii) Change in the direction of wind and ocean currents.
 
ECLIPSES
When the light of the sun or the moon is obscured by another body the sun or moon is said to be in eclipse.

Lunar Eclipse: The moon is said to be in eclipse when the earth comes between the moon and the sun, and this is called Lunar eclipse. The shadow cast by the earth on the moon is called an eclipse.
Lunar eclipse occurs only on a full moon day. However, it does not occur on every full moon day because the moon is not in the same position in relation to the earth and the sun on every full moon day.

Solar Eclipse: The sun is said- to be in eclipse when the moon comes between the sun and the earth. This is called Solar eclipse. There is either a partial or total obstruction of the sun's light when viewed from the earth. A solar eclipse occurs on a new moon day when the moon is in line with the sun. However, due to the inclination of the moon's orbit, a solar eclipse does not occur on every new moon day.
 
ATMOSPHERE
The atmosphere is a gaseous en­velope that surrounds a celestial body. The terrestrial atmosphere, by nature of its composition, control of temperature and shielding effect against solar radiation, makes life possible on earth. It covers both the land and the water surface. It is bound to the earth by the gravitational pull of the earth. The composition of the atmosphere changes as we go higher from the earth's surface. Upto about a height of 50 km from the earth, the atmosphere is composed of:
Nitrogen 78.09%
Oxygen 20.95%
Argon 0.93%
Minor gases (Carbon dioxide, hydrogen, neon, helium, methane, xenon, krypton, etc.) 0.03%

After a height of 50 km above the earth's surface the atmosphere is made up of atomic oxygen (O2), ozone (O3), helium and hydrogen.

Atmospheric Layers
These are the layers of air that lie above the earth's surface. The atmosphere of the earth is arranged into layers as accrued below, viz.

Troposphere: The troposphere is the layer nearest to the earth's surface and extends from sea-level to a height of about 15 km. This region is the densest of all the atmospheric layers and contains water vapour, moisture and dust. In this region the temperature decreases as the height increases from the earth.

Tropopause: Tropopause is the layer which separates the troposphere (lowest layer) from the stratosphere (upper layer).

Stratosphere: This is the region of uniform temperature extending from an altitude of about 15km above the earth to a height of about 50 kill. It is free from water vapour, clouds and dust.

Mesosphere: This is a very cold region and lies above the ozone-rich layer of the stratosphere. It extends from 50 or 80 km above the earth's surface.

Menopause: The Menopause separates the mesosphere from the next layer called the ionosphere.

Ionosphere: The ionosphere lies immediately above the mesosphere and extends from 60 to 400 km above the earth's surface. This layer contains ionised (or electrically charged) air which protects the earth from the falling meteorites (shooting stars) as most of them burn out in this region. It also protects the earth from the harmful radiations of the sun. The ionosphere consists of ‘D’, ‘E’ and ‘F’ layers and includes the thermosphere and exosphere.

Thermosphere: This is the middle layer of the ionosphere. It is the region of the atmosphere where the temperature is above 100°C.

Exosphere: The exosphere is the uppermost region of the ionosphere and makes up the outer limits of the atmosphere. Here the gravity of the earth is exceedingly weak. The magnetic belt of the earth which is known as Magnetosphere, extends to about 64,000 km above the earth's surface. The exosphere is now considered as part of the magnetosphere. The outer boundary of the magnetosphere or the final boundary between the earth and outer space is known its magnetopause.

The land surface of the earth is made up of immense land masses divided into seven continents and a great number of islands. Together, they cover about one quarter of the earth's surface.

It is believed that originally there was only one land mass called Pangaea. This large land mass split into a northern mass Laurasia and a southern one called Gondwana Land. From these two land masses, the continents gradually drifted to where they are now located and the process is still continuing.