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]

ii.2. Description of Sound Waves: Frequency, Amplitude, and Speed Essentials

Sound waves can be described by its 

  • a) Frequency, 
  • b) Amplitude and 
  • c) Speed

Frequency

  • It refers to the number of oscillations or vibrations per unit of time. 
    • In the context of sound, it determines the pitch of the sound.  
    • If we can count the number of the compressions or rarefactions that cross us per unit time, we will get the frequency of the sound wave.
    • Unit: Hertz (Hz) is used to measure frequency, which represents one cycle per second.
    • High Frequency Sounds: It has a high pitch, like a whistle or a bird’s chirp. 
    • Low Frequency Sounds: It has a low pitch, like the rumble of thunder. 
    • Example: The frequency of a typical conversation is about 300 to 3,000 Hz.

Amplitude

  • It refers to the maximum displacement or distance moved by a point on a vibrating body or wave from its equilibrium position during one complete vibration. 
    • In the context of sound, it determines the loudness or intensity of the sound. 
    • Unit: The unit of amplitude is usually measured in decibels (dB) in acoustics.

Sound propagates as density or pressure variations as shown in (a) and (b), (c) represents graphically the density and pressure variations.

  • Example: A loud shout will have a greater amplitude compared to a soft whisper.

Speed

  • Speed of sound is the distance travelled per unit time by a sound wave as it propagates through a medium.
    • Unit: The speed of sound is typically measured in metres per second (m/s).
    • The speed of sound varies depending on the medium. 
    • In air, at a temperature of about 20°C, it’s approximately 343 metres per second.
    • Example: In dry air at 20°C, sound travels at around 343 metres per second.

[Low pitch sound has low frequency and high pitch of sound has high frequency]