HIMALAYAN TUNNELS 

West → East Order (with Mountain Range)

North → South Order

Important Facts

• Longest Road Tunnel → Atal Tunnel (9.02 km, Himachal Pradesh)
• Longest Railway Tunnel → Pir Panjal Tunnel (11.215 km, J&K, 1760 m altitude)
• Highest Tunnel → Sela Tunnel (~13000 ft, Arunachal Pradesh, BRO)

VOLCANO (SHIELD TYPE)

• Low silica
• Low viscosity
• Lava flows easily

Examples: Hawaiian volcanoesIn News:

• Hayli Gubbo (Ethiopia)
• Kilauea (Hawaii)
• Nyamuragira (DR Congo)

ROCKS CLASSIFICATION

Igneous Rocks

• Intrusive (Plutonic): Granite, Gabbro
• Extrusive (Volcanic): Rhyolite, Basalt, Obsidian

Sedimentary Rocks

• Clastic: Sandstone, Conglomerate
• Chemical: Limestone, Gypsum
• Organic: Coquina

Metamorphic Rocks

• Foliated: Gneiss, Slate
• Non-foliated: Marble, Hornfels

EARTHQUAKE TERMS

• Focus / Hypocentre → Origin inside Earth
• Epicentre → Point above focus on surface

RIVER BASIN ORDER

Godavari > Krishna > Mahanadi > Narmada

INDIAN POLITY

Interim Government

• Till Feb 1947 → Wavell
• After → Lord Mountbatten

Constituent Assembly

• First meeting → 9 December 1946
• Objective Resolution → 22 January 1947

Important Dates

• 24 January 1950 → National Anthem adopted (Jana Gana Mana)

ARTICLES (COMPARATIVE ANALYSIS)

Direct Comparison

ATTORNEY GENERAL

• Qualification → Same as Supreme Court Judge
• Removal → Like CEC

CBI & CVC

• CBI Act → 2002
• CVC Act → 2003
• CVC → Statutory status (1998)

FUNDAMENTAL DUTIES (Article 51A)

DIRECTIVE PRINCIPLES (DPSP)

Article 38

• Promote welfare
• Social, economic, political justice

Article 39 (a–f)

Article 43

• Cottage industries in rural areas

Article 43B

• Promotion of cooperative societies (97th Amendment, 2011)

Article 47

• Improve nutrition
• Improve public health
• Raise standard of living
• Prohibit intoxicating drinks and drugs

FUNDAMENTAL RIGHTS – RESTRICTIONS

• Article 13 → Laws inconsistent with Fundamental Rights are void
• Article 33 → Restriction for armed forces, intelligence agencies, public order forces
• Article 34 → During martial law
• Article 35 → Only Parliament can legislate

CONCURRENT LIST (42–76)

• Education
• Forest
• Weights and measures
• Protection of wild animals and birds
• Administration of justice

EXECUTIVE ACTION

• Article 200 → Governor
• Article 201 → President

PARDONING POWERS (Article 72)

Scope

• Court martial
• Union laws
• Death sentence

Types

• Pardon
• Commutation
• Remission
• Respite
• Reprieve

FINAL REVISION KEY POINTS

• Atal Tunnel → Pir Panjal Range
• Zojila → Great Himalaya
• Pir Panjal Tunnel → Railway
• Articles 77–78 → Union
• Articles 166–167 → State
• Article 51A(g) → Environment
• Article 39(d) → Equal pay
• Article 43B → Cooperative societies
• Article 47 → Public health

STRUCTURE OF THE EARTH, VOLCANOES & EARTHQUAKES

STRUCTURE OF THE EARTH

The Crust

The crust is the outermost solid layer of the earth and is brittle in nature. Its thickness varies between oceanic and continental regions. The oceanic crust is thinner with an average thickness of about 5 km, whereas the continental crust has an average thickness of around 30 km. In major mountain regions like the Himalayas, it can reach up to 70 km, making it the thickest part of the crust.

The Mantle

The mantle lies beneath the crust and extends from the Moho discontinuity to a depth of about 2,900 km. The upper portion of the mantle is known as the asthenosphere, extending up to 400 km. It is a weak zone and serves as the main source of magma responsible for volcanic eruptions.The lithosphere consists of the crust and uppermost mantle, with a thickness ranging from 10–200 km. Below the asthenosphere lies the lower mantle, which is in a solid state.

The Core

The core begins at a depth of 2,900 km (core-mantle boundary). It is composed mainly of nickel and iron (NiFe layer). The outer core is liquid, while the inner core is solid. The existence and structure of the core have been understood through earthquake wave studies.

VOLCANOES AND VOLCANIC LANDFORMS

Volcanoes

A volcano is an opening through which gases, ash, and molten rock (lava) escape to the surface. If such activity has occurred recently, it is termed an active volcano. The molten material beneath the crust is called magma, and once it reaches the surface, it is called lava.Volcanic materials include:

• Lava flows
• Pyroclastic debris
• Volcanic bombs
• Ash and dust
• Gases (nitrogen, sulphur compounds, chlorine, hydrogen, argon)

Types of Volcanoes

Shield Volcanoes

These are the largest volcanoes, mostly composed of basaltic lava, which is highly fluid. Hence, they have gentle slopes and low explosivity. Example: Hawaiian volcanoes.

Composite Volcanoes

These are formed by viscous lava eruptions along with pyroclastic material. They are characterized by explosive eruptions and layered structure around the vent.

Caldera

These are formed by extremely explosive eruptions leading to collapse and formation of a large depression instead of a cone. Indicates a large magma chamber.

Flood Basalt Provinces

These involve extensive outpouring of fluid lava, covering vast areas. Example: Deccan Traps (India).

Mid-Ocean Ridge Volcanoes

These occur along mid-ocean ridges (over 70,000 km long) with frequent eruptions in ocean basins.

VOLCANIC LANDFORMS (INTRUSIVE FORMS)

Intrusive forms develop when magma cools within the crust.

Batholiths

Large granitic bodies formed deep inside the crust; exposed after erosion.

Lacoliths

Dome-shaped intrusions with a flat base and connected to magma source below.

Lapolith

A saucer-shaped intrusion, concave upward.

Phacolith

Wavy intrusions found at anticline tops or syncline bases, connected to magma source.

Sills 
Horizontal intrusions; thicker ones are sills, thinner ones are sheets.

Dykes

Vertical, wall-like structures formed when magma solidifies in cracks; common in Deccan region.

EARTHQUAKE WAVES

Earthquakes originate in the lithosphere (up to 200 km depth) and are recorded using a seismograph.

Types of Waves

Body Waves

Travel through the interior of the earth:

• P-waves (Primary waves): Fastest, travel through solids, liquids, and gases
• S-waves (Secondary waves): Slower, travel only through solids

Surface Waves

Travel along the surface and are the most destructive.

Propagation of Waves

• P-waves vibrate parallel to the direction of movement causing compression and expansion
• S-waves vibrate perpendicular, creating troughs and crests
• Wave velocity increases with density of material
• Waves undergo reflection and refraction when encountering different densities

SHADOW ZONE

A shadow zone is an area where earthquake waves are not detected.

• Between 105° and 145° from the epicentre → No P and S waves
• Beyond 105° → No S-waves
• P-waves reappear beyond 145°
• S-wave shadow zone covers over 40% of Earth’s surface

TYPES OF EARTHQUAKES

• Tectonic earthquakes: Due to fault movement (most common)
• Volcanic earthquakes: Associated with active volcanoes
• Collapse earthquakes: Due to mine roof collapse
• Explosion earthquakes: Due to chemical/nuclear explosions
• Reservoir-induced earthquakes: Due to large dams/reservoirs

MEASURING EARTHQUAKES

• Richter Scale: Measures magnitude (energy released), range 0–10
• Mercalli Scale: Measures intensity (damage caused), range 1–12

KEY TAKEAWAY (EXAM FOCUS)

• Asthenosphere = source of magma
• S-waves do not travel through liquids → proves liquid outer core
• Shadow zone concept explains Earth’s internal structure
• Deccan Traps = Flood Basalt Province
• Lithosphere = crust + upper mantle (10–200 km)

AD HOC JUDGES IN INDIA – CONSOLIDATED NOTES

Introduction

Ad hoc judges in India are temporary judicial appointments made to address case backlogs and vacancy gaps in higher judiciary. These appointments are governed by constitutional provisions under Articles 224A, 127, and 128, and require both consent of the judge and approval of the President of India.

Who Can Be Appointed as Ad Hoc Judges?

1. High Court (Article 224A)

• A retired judge of a High Court can be requested to sit and act as a High Court judge.

2. Supreme Court (Article 127)

• A sitting judge of a High Court, who is duly qualified to be a Supreme Court judge, can be requested to attend as an ad hoc judge of the Supreme Court.

3. Supreme Court (Article 128)

• A retired Supreme Court judge or a retired High Court judge (duly qualified) can be requested to sit and act as a judge of the Supreme Court.

Key Requirements and Conditions

Consent

• The retired or serving judge must give consent before appointment.

Approval

• Appointment requires prior approval of the President of India.

Role Limitation

• In High Courts, ad hoc judges generally handle long-pending cases (often over 5 years old) or criminal appeals.
• They usually function alongside a sitting judge.

Tenure

• Typically appointed for 2 to 3 years, though the duration may vary.

Emoluments

• They receive pay and allowances similar to a sitting judge, but pension is excluded.

Conclusion

The system of ad hoc judges acts as a temporary institutional mechanism to strengthen judicial capacity, ensuring speedy disposal of pending cases while maintaining constitutional safeguards like consent and presidential approval.

EVM Development Timeline

• 1982 → First use of EVM (trial basis) in Parur Assembly Constituency, Kerala
• 1989 → Legal provision for voting machines introduced
• 1993 → Decision taken to issue EPIC (Elector Photo Identity Card)
• 1998 → EVMs used in Rajasthan, MP, Delhi Assembly elections (select constituencies)
• 1999
  • Used in 46 constituencies in General Elections (partial use)
  • First use in Goa Assembly Election
• 2001–02 → States like Tamil Nadu, Puducherry, Kerala adopted EVMs comprehensively
• 2003 → Proxy voting facility introduced for armed forces
• 2004 → EVMs used across entire country in General Elections

HIND SWARAJ (1909) – M.K. Gandhi

• Hind Swaraj is a philosophical critique of modern Western civilization, written in 1909.
• Gandhi defined Swaraj not merely as political independence, but as self-rule based on moral and spiritual discipline.
• He criticised industrialisation, materialism, and institutions like railways, lawyers, and doctors as tools of exploitation.
• Emphasised Truth (Satya), Non-violence (Ahimsa), and Swadeshi (self-reliance) as the foundation of society.
• Written in a dialogue form (Editor vs Reader), making it a unique political text.
• Impact: Provided the ideological foundation of India’s freedom struggle, promoting ethical politics and mass awakening.

SARVODAYA (Concept by Gandhi)

• Sarvodaya means “Welfare of All”, inspired by John Ruskin’s “Unto This Last”.
• It advocates inclusive development, where every individual, especially the weakest (Antyodaya), is uplifted.
• Based on principles of equality, dignity of labour, decentralisation, and non-violence.
• Promotes a village-based, self-reliant economy with emphasis on social justice.
• Found practical expression in Vinoba Bhave’s Bhoodan Movement (1951) and later Gramdan.
• Impact: Strengthened ideas of social equality, rural development, and non-violent transformation in Indian society.

EVOLUTION OF TAXATION IN INDIA)

ANCIENT & COLONIAL PERIOD

• Ancient India → Tax in form of “Shulka” (custom duty on goods at borders)
• 1860→
  • Income Tax introduced on 24 July 1860
  • Introduced by Sir James Wilson (first Finance Member of British India)
  • Purpose → Post-1857 financial crisis
• 1860→
  • Corporate Tax introduced
  • By Sir James Wilson
• 1878→
  • Sea Customs Act, 1878
  • Established formal system of customs duties (import/export)

POST-INDEPENDENCE TAX DEVELOPMENTS

• 1944→
  • Central Excise Act, 1944
  • Provided centralised framework for taxing manufactured goods
  • Still applicable for items outside GST
• 1947 (Budget, AY 1947–48)→
  • Capital Gains Tax introduced
  • Via amendment to Income Tax Act, 1922
  • Purpose → Tax speculative profits post-WWII
• 1949→
  • Capital Gains Tax abolished
• 1956 (Finance Act No. 3)→
  • Capital Gains Tax reintroduced permanently
  • Based on recommendation of Nicholas Kaldor
• 1957 (Wealth Tax Act, 1957)→
  • Enacted on 12 September 1957
  • Effective from 1 April 1957
  • Applied to:
    • Individuals
    • HUFs
    • Companies
  • Objective → Reduce inequality (tax on net wealth)
• 2015→
  • Wealth Tax abolished

MODERN TAX REFORMS (LIBERALISATION ERA)

• 2004 (1 October)→
  • Securities Transaction Tax (STT) introduced
  • Under Finance Act, 2004
  • By Finance Minister P. Chidambaram
• 2003→
  • Haryana first to implement VAT (early phase)
• 2005 (1 April)→
  • VAT introduced across most states
  • Replaced sales tax system
  • Objective → Reduce cascading effect + improve transparency

CUSTOMS & INDIRECT TAX FRAMEWORK

• 1962→
  • Customs Act, 1962
  • Replaced colonial laws
  • Established unified control over:
    • Air
    • Land
    • Sea trade

UNIFIED TAX SYSTEM (GST ERA)

• 2016→
  • 101st Constitutional Amendment Act
  • Provided legal foundation for GST
• 1 July 2017→
  • GST (Goods and Services Tax) launched
  • Replaced multiple central + state indirect taxes
  • Launched in midnight session of Parliament
  • By:
    • President Pranab Mukherjee
    • PM Narendra Modi
  • Objective → One Nation, One Tax