External processes

  1. External processes are geomorphic activities that originate from forces outside the Earth's surface.
  2. These processes are also called exogenic processes.
  3. They include weathering, erosion, transportation, and deposition.
  4. External processes are driven by solar energy, gravity, and the hydrological cycle.
  5. Weathering is the breakdown of rocks into smaller particles through physical, chemical, or biological means.
  6. Physical weat

Solar system

  1. The Solar System consists of the Sun, eight planets, moons, dwarf planets, asteroids, comets, and other celestial objects.
  2. The Sun is the center of the Solar System and accounts for 99.86% of its total mass.
  3. The eight planets are classified as terrestrial planets (Mercury, Venus, Earth, Mars) and gas giants (Jupiter, Saturn) and ice giants (Uranus, Neptune).
  4. Mercury is the closest planet to the Sun and has no atmosphere to retain heat.
  5. Venus

Earth's motions

  1. The Earth has two primary motions: rotation and revolution.
  2. Rotation refers to the Earth spinning on its axis.
  3. The Earth completes one rotation in approximately 24 hours, causing day and night.
  4. The axis of rotation is tilted at an angle of 23.5° relative to the plane of its orbit.
  5. Revolution refers to the Earth's orbit around the Sun.
  6. One complete revolution takes approximately 365.25 days, leading to the concept of a year.

Structure of the Earth

  1. The Earth is divided into three main layers: the core, mantle, and crust.
  2. The crust is the Earth's outermost layer, comprising solid rocks and minerals.
  3. The thickness of the crust varies from 5 km under oceans to 70 km under continents.
  4. The crust is divided into the continental crust and oceanic crust.
  5. The continental crust is primarily composed of granite, while the oceanic crust is made of basa

Origin of the Earth

  1. The Earth is a part of the Solar System, which includes the Sun, eight planets, and other celestial bodies.
  2. The Big Bang Theory explains the origin of the universe approximately 13.8 billion years ago.
  3. The Solar System is believed to have formed about 4.6 billion years ago.
  4. The nebular hypothesis proposed by Immanuel Kant and Pierre-Simon Laplace suggests the Solar System formed from a rotating cloud of gas and dust.
  5. The protostar at the center of the nebula eventually b

Modern Developments

  1. The adoption of the Constitution of India in 1950 established India as a sovereign, secular, socialist, democratic republic.
  2. The Green Revolution (1960s–1970s) transformed India’s agriculture, achieving self-sufficiency in food grains.
  3. The White Revolution, spearheaded by Verghese Kurien, made India the largest producer of milk and dairy products.
  4. India’s space program, led by ISRO, achieved significant milestones, including the

Wars and Conflicts

  1. The First Indo-Pak War (1947–1948) occurred over the princely state of Jammu and Kashmir and ended with a UN-mediated ceasefire.
  2. The conflict led to the division of Jammu and Kashmir into areas controlled by India and Pakistan.
  3. The Sino-Indian War (1962) arose due to border disputes in Aksai Chin and Arunachal Pradesh.
  4. The 1962 war exposed India's military weaknesses and led to reforms in defense preparedness.
  5. The

Five-Year Plans and Economic Reforms

  1. The concept of Five-Year Plans in India was inspired by the Soviet model of economic planning.
  2. The Planning Commission was established in 1950 under the chairmanship of Prime Minister Jawaharlal Nehru.
  3. India’s first Five-Year Plan was launched in 1951 with a focus on agriculture and irrigation.
  4. The first plan was successful and achieved a growth rate of 3.6%, higher than the target of 2.1%.
  5. The Second Five-Year Plan (195

Constitution of India (1950)

  1. The Constitution of India was adopted on 26th November 1949 by the Constituent Assembly.
  2. It came into effect on 26th January 1950, a date celebrated annually as Republic Day.
  3. The drafting of the Constitution was led by the Constituent Assembly, formed in 1946.
  4. The Drafting Committee, chaired by Dr. B.R.

Partition and Integration of Princely States

  1. At the time of independence in 1947, India consisted of 565 princely states alongside British-administered territories.
  2. These princely states were given the choice to join India, Pakistan, or remain independent.
  3. The task of integrating these states was led by Sardar Vallabhbhai Patel, the first Deputy Prime Minister and Home Minister of India.
  4. Patel, along with V.P.