Course Content
UPSC Notes Samples
Full Syllabus Covered | 100% as per Official UPSC Syllabus
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1. Art & Culture Sample
Covered under topic 1. Indian culture will cover the salient aspects of Art Forms, Literature and Architecture from ancient to modern times.
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1. Indian culture will cover the salient aspects of Art Forms, Literature and Architecture from ancient to modern times. (copy)
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2. Modern Indian history from about the middle of the eighteenth century until the present- significant events, personalities, issues. (copy)
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5. History of the world will include events from the 18th century such as Industrial revolution, World wars, Redrawal of national boundaries, Colonization, Decolonization, Political philosophies like Communism, Capitalism, Socialism etc.- their forms and effect on the society.
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7. Role of women and women’s organizations, Population and associated issues, Poverty and developmental issues, Urbanization, their problems and their remedies.
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10.2. Introduction to Maps
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GS2
All topics that need updates are given below.
2. Functions and responsibilities of the Union and the States, issues and challenges pertaining to the federal structure, devolution of powers and finances up to local levels and challenges therein.
All topics that need updates are given below.
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5. Parliament and State Legislatures – structure, functioning, conduct of business, powers & privileges and issues arising out of these.
All topics that need updates are given below.
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6. Structure, organization and functioning of the Executive and the Judiciary; Ministries and Departments of the Government; pressure groups and formal/informal associations and their role in the Polity.
All topics that need updates are given below.
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12. Welfare schemes for Vulnerable Sections of the Population by the Centre and States and the Performance of these schemes; Mechanisms, Laws, Institutions and Bodies constituted for the Protection and Betterment of these Vulnerable Sections.
All topics that need updates are given below.
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GS3
All topics that need updates are given below.
11. Science and Technology- developments and their applications and effects in everyday life.
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GS3: BIODIVERSITY AND ENVIRONMENT
All topics that need updates are given below.
1. Environment
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GS4
All topics that need updates are given below.
GS3: SCIENCE AND TECHNOLOGY
All topics given below
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1. Motion & Measurements
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9. Metals & Non-Metals
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10. Energy
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12. Plant Organisms
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14. Life Processes
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18. Biotechnology
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19. Information Technology
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20. Space Technology
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National & International Current Affairs (CA) 2025
Current affairs of all months are given below
delete UPSC Sample Notes [English]

iv.4.  How did Bohr reshape Atomic Structure with Discrete Electron Orbits and Energy Levels?

Overcoming Objections with Key Postulates

  • In order to overcome the objections raised against Rutherford’s model of the atom, Neils Bohr put forward the following postulates: 
    • Only certain special orbits known as discrete orbits of electrons, are allowed inside the atom. 
    • While revolving in discrete orbits the electrons do not radiate energy, a crucial aspect of atomic structure stability.
  • These orbits or shells are called energy levels . 
  • These orbits or shells are represented by the letters K,L,M,N,… or the numbers, n=1,2,3,4,…., illustrating the hierarchical arrangement in the atomic structure.

A few energy levels in an atom