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]

x.1. Dynamics of Mass and Weight in Physics

Mass and weight are related but distinct concepts in physics. Mass is a measure of the amount of matter in an object, typically measured in kilograms or grams. It is an intrinsic property and remains constant regardless of the object’s location. Weight, on the other hand, is the force exerted on an object due to gravity and is measured in newtons. Weight depends on both mass and the acceleration due to gravitation.

Mass: The Intrinsic Measure of Matter’s Resistance to Change

  • Definition: Mass is a measure of the amount of matter contained in an object.
  • Inertia and Mass: The more mass an object has, the more inertia it possesses. 
    • Inertia is the resistance of any physical object to any change in its state of motion.
  • Constancy: The mass of an object remains the same regardless of its location. 
    • Whether the object is on Earth, the Moon, in outer space, or anywhere else in the universe, its mass will not change. 
    • This property makes mass a scalar and universal quantity.

Weight: The Dynamic Interaction of Mass, Gravity, and Force

  • Definition: Weight is the force exerted on an object due to gravity. 
    • It’s the force with which an object is attracted towards a massive body, such as a planet.
  • Relation between Mass and Weight: Particular eight is dependent on both the mass of an object and the acceleration due to gravitation at that location. 
    • Mathematically, it can be represented as: 

W=m×g 

Where: 

W = Weight of the object (in newtons) 

m = Mass of the object (in kilograms) 

g = Acceleration due to gravity.

  • Units: Since weight is a force, its SI unit is the Newton (N).
  • Direction: Weight is a vector quantity as it has both magnitude (how much force) and direction (towards the center of the massive body, usually downwards towards the center of the Earth).
  • Variability: Weight of an object can vary depending on where the object is. 
    • For instance, an object would weigh less on the Moon than on Earth due to the Moon’s lower gravitational acceleration. 
    • Conversely, the mass of that object remains constant regardless of location.
  • Measuring Mass via Weight: In everyday life and many standard conditions on Earth, because g is relatively constant, we often use weight to indirectly measure mass. 
    • When we say something “weighs” 10 kilograms, technically this is a misuse of terms, but it is understood colloquially because of the consistent gravity on Earth’s surface.
  • Mass as Scalar Quantity: While mass is a scalar quantity that remains constant regardless of an object’s location, weight is a vector quantity that can vary based on local gravitational forces. 
    • This distinction is crucial in fields such as physics, astronomy, and space exploration, where objects may be observed or used in various gravitational environments.

Weight on the Moon: Exploring Lunar Gravitational Influence

  • Concept: Just as objects possess mass and weight on Earth due to the gravitational force exerted by the Earth, they also exhibit mass and weight on the Moon owing to the Moon’s gravitational force. 

However, the Moon’s gravitational force is weaker than Earth’s because the Moon has less mass.

  • Comparison with Earth: The weight of an object on the Moon is one-sixth (1/6) of its weight on Earth. 
    • This means that if you weigh 60 kg on Earth, you would weigh only 10 kg on the Moon.

Example:  Mass of an object is 10 kg. What is its weight on the earth? 

Solution: 

Mass, m = 10 kg
Acceleration due to gravity, g = 9.8 m s–2 

W=m×g 

W=10kg×9.8ms-2 =98N

Thus, the weight of the object is 98 N.