There are 4 NCERT texts that tackle geography which are required to be covered and often enough to cover the basics of questions coming in prelims. These are for classes 11, 12 and cover physical and human geography of world and India. I have tried to summarize them for quick look through.
Aim here is to compile some stuff that will help you punch out the straight out of book questions. Kindly pardon some extra detail I have slipped in here and there. I will mark it using <XDS> meaning extra detail start and <XDE> extra detail ends
Fundamentals of Physical Geography of Class XI
Chapter 1 Geography as a discipline
--term geography coined by Greek scholar Erastosthenes, means geo=earth, graphos=description
--2 major approaches to geography
-systematic by Alexander Von Humboldt
-regional by Karl Ritter
(both are German(or should we say Prussian) geographers and of about same time frame in 18th century)
Systematic approach branches out geography into physical(geomorphology, hydrology, climatology, soil geography), human(social/cultural, settlement wise, economic, historical, political), biological(plant, zoo, ecology, environmental)
Regional approach branches out as Regional studies, planning, development and analysis, further branching out into macro, meso and micro under each head
Chapter 2 Origin and evolution of earth
Immanuel Kant, 1796, Nebular hypothesis--planets formed out of cloud material(nebula) related to sun
Chamberlain and Moulton, 1900, wandering star comes to sun, cigar shape separates out of sun...
Later, binary theories, say this other star was coexisting with sun
Otto Schmidt(Russia), Carl Weizascar(Germany), 1950, revise Nebular hypothesis saying this cloud stuff by friction, collision--->accretion led to disk shape and then planets
<XDS>So there is nebula(cloud stuff) in which there is a star and around it is the circum(round)+stellar(star) disc which can be protoplanetary disc or an accretion disc. Fascinating thing is that accretion can be understood as process of planets sweeping and picking up stuff, growing. But actually there are other systems where accretion takes place from outer edge of disc towards the star/center. Like the magnetic field in a toroid/doughnut. One can only imagine, how fascinating the momentum distribution might be working in such system.<XDE>
1920 Edwin Hubble gave Expanding universe hypothesis or Big bang theory(not the TV show)
Some big units of length: Light-year=9.46e12 km, Astronomical Unit=1.496e8 km(sun to earth avg), <XDS>parsec=3.086e13km[distance at which one astronomical unit subtends an angle of one arcsecond]<XDE>
<XDS>Life of a star:
This single picture is enough to understand stellar evolution: https://en.wikipedia.org/wiki/File:Star_life_cycles_red_dwarf_en.svg
so, low mass star life cycle: nebula-protostar-red dwarf-white dwarf-blue dwarf-black dwarf
mid-size star: nebula-protostar-red giant-planetary nebula-white dwarf-black dwarf
big star: nebula-protostar-massive star-red supergiant-supernova
supernova blows up outer layers while remaining core can become neutron star if small, a black hole if massive
Now, Chandrashekhar limit is 1.39 x mass of sun(Ms) and is the max mass of a stable white dwarf star, calculated by S Chandreshekhar at age of 19. Lets understand what it means. As star gains power by nuclear fusion, at core lighter elements like hydrogen fuse and form heavier elements like Helium. Now, there is a phenomenon in quantum physics which does not allow certain particles(called Fermions) like electrons to have same energy level. So, cant allow degeneracy. This creates pressure which counters inwards gravitational pull. Beyond certain mass limit, pressure is not enough and star collapses on itself and cant be a stable white dwarf, hence the limit.<XDE>
Solar system formed 4.6 bn years ago
<XDS>
Sun: 99.86% of solar system mass, 3/4th of it is hydrogen by mass, has layers Core, Radiative zone, Tachocline(transition layer), Convective zone, photosphere(visible surface of sun)
Sun's atmosphere is hotter than the surface, has 3 layers--chromosphere(colored), transition zone, corona(hottest layer)
Beyond this is heliosphere(where solar winds flow), extending beyond Neptune and protecting planets from interstellar medium
Inner/terrestrial/earth-like planets: mercury, venus, earth, mars
Inferior planets: closer to sun than earth=mercury, venus and others/farther are superior planets
Asteroids: largest is Ceres
Outer/jovian/jupiter-like: Gas giants-- Jupiter, Saturn, Ice giants-- Uranus, Neptune
Kuiper belt: a circumstellar orbit beyond Neptune's orbit(30AU) to ~55AU from sun, has 3 officially recognized dwarf planets--Pluto, Haumea, Makemake
Oort cloud: much more on the outside is the inner Oort cloud disc shaped AKA Hills cloud and further is outer Oort cloud, spherical upto 1,00,000 AU
More on planets:
IAU 2006 definition of planet: 3 criteria--1.orbits around sun, 2.mass enough to assume round shape, 3.has cleared its neighbourhood(stuff in its orbit)
If only 1,2 satisfied then it is a dwarf planet like Pluto
Mercury: named after Roman deity Mercury, messenger to gods and NASA had sent MESSENGER to it(launched 2004, ran out of fuel in 2015)
Venus: hottest planet, named after Roman goddess of love and beauty, earth's sister planet, 96% CO2 in atmosphere, highly reflective sulfuric acid clouds make atmosphere opaque, Magellan orbiter 1991
Mars: Roman god of war, has 2 moons Phobos(fear, hence phobia), Deimos(terror), MAVEN and MOM are orbiting it, on surface we have Opportunity rover and Curiosity
Jupiter: largest, named after Roman god of sky and thunder, eq to Greek Zeus, 67 moons, 4 large Galilean moons--Io, Europa, Ganymede, Callisto named after lovers of Zeus
Saturn: Roman god of agriculture, 62 moons, largest moon Titan(brothers/sisters of Greek equivalent god Cronus), Cassini-Huygens space probe
Uranus: only planet named after Greek god(of sky), apart from hydrogen and helium in atmosphere has "ices"--water, ammonia, methane, trace hydrocarbons, 27 moons largest is Titania
Neptune--Roman god of sea, 14 moons largest is Triton(has retrograde orbit), Voyager 2 is only spacecraft to visit it
All planets revolve in same direction around sun in anti-clockwise orbit. Also all planets rotate in same direction as sun (prograde) except. venus that rotates in reverse direction(retrograde) on its own axis, while Uranus has an axis almost horizontal(tilted by 90deg)
<XDE>
13.7BYA big bang, 5-6 BYA stars formed, 5-5.6BYA solar system formed, 4.6BYA planets formed, 4.44BYA moon formed, 4BYA oceans formed on earth, 3.8BYA life began, 2.5-3 BYA photosynthesis got evolved, 2BYA oxygen began to flood atmosphere
On time scale: Eons>Era>Period>Epoch>Age/years
currently we are in Cainozoic era, Quaternary period, Holocene epoch
Evolution of earth
--of lithosphere: process of differentiation(cooling, density change, material moves, layer formation)
--3 stages of atmosphere, hydrosphere: 1.loss of primordial atmosphere due to solar winds, 2. degassing--interior gas released, 3.photosynthesis
Chapter 3 Interior of Earth
Sources of information:
Direct: rocks from mining, deep drilling, volcanic eruptions
Indirect: PVT(pressure, volume/density, temperature) estimates at different depths, gravitation, magnetic field and seismic activity studies
Earthquake: source point=focus=hypocentre, closest point on surface to focus=epicenter
Types of earthquake waves
Aim here is to compile some stuff that will help you punch out the straight out of book questions. Kindly pardon some extra detail I have slipped in here and there. I will mark it using <XDS> meaning extra detail start and <XDE> extra detail ends
Fundamentals of Physical Geography of Class XI
Chapter 1 Geography as a discipline
--term geography coined by Greek scholar Erastosthenes, means geo=earth, graphos=description
--2 major approaches to geography
-systematic by Alexander Von Humboldt
-regional by Karl Ritter
(both are German(or should we say Prussian) geographers and of about same time frame in 18th century)
Systematic approach branches out geography into physical(geomorphology, hydrology, climatology, soil geography), human(social/cultural, settlement wise, economic, historical, political), biological(plant, zoo, ecology, environmental)
Regional approach branches out as Regional studies, planning, development and analysis, further branching out into macro, meso and micro under each head
Chapter 2 Origin and evolution of earth
Immanuel Kant, 1796, Nebular hypothesis--planets formed out of cloud material(nebula) related to sun
Chamberlain and Moulton, 1900, wandering star comes to sun, cigar shape separates out of sun...
Later, binary theories, say this other star was coexisting with sun
Otto Schmidt(Russia), Carl Weizascar(Germany), 1950, revise Nebular hypothesis saying this cloud stuff by friction, collision--->accretion led to disk shape and then planets
<XDS>So there is nebula(cloud stuff) in which there is a star and around it is the circum(round)+stellar(star) disc which can be protoplanetary disc or an accretion disc. Fascinating thing is that accretion can be understood as process of planets sweeping and picking up stuff, growing. But actually there are other systems where accretion takes place from outer edge of disc towards the star/center. Like the magnetic field in a toroid/doughnut. One can only imagine, how fascinating the momentum distribution might be working in such system.<XDE>
1920 Edwin Hubble gave Expanding universe hypothesis or Big bang theory(not the TV show)
So, ~13.7 bn years ago ka-boom.
<XDS>Hubble says v=H D meaning velocity of an object is Hubble constant times "proper distance" to that object. So, a galaxy further away is moving faster away from us. So, clearly it is accelerating, and where is it getting energy to do so? The answer is dark energy. Still largely a mystery. <XDE>
<XDS>Hubble says v=H D meaning velocity of an object is Hubble constant times "proper distance" to that object. So, a galaxy further away is moving faster away from us. So, clearly it is accelerating, and where is it getting energy to do so? The answer is dark energy. Still largely a mystery. <XDE>
Some big units of length: Light-year=9.46e12 km, Astronomical Unit=1.496e8 km(sun to earth avg), <XDS>parsec=3.086e13km[distance at which one astronomical unit subtends an angle of one arcsecond]<XDE>
<XDS>Life of a star:
This single picture is enough to understand stellar evolution: https://en.wikipedia.org/wiki/File:Star_life_cycles_red_dwarf_en.svg
so, low mass star life cycle: nebula-protostar-red dwarf-white dwarf-blue dwarf-black dwarf
mid-size star: nebula-protostar-red giant-planetary nebula-white dwarf-black dwarf
big star: nebula-protostar-massive star-red supergiant-supernova
supernova blows up outer layers while remaining core can become neutron star if small, a black hole if massive
Now, Chandrashekhar limit is 1.39 x mass of sun(Ms) and is the max mass of a stable white dwarf star, calculated by S Chandreshekhar at age of 19. Lets understand what it means. As star gains power by nuclear fusion, at core lighter elements like hydrogen fuse and form heavier elements like Helium. Now, there is a phenomenon in quantum physics which does not allow certain particles(called Fermions) like electrons to have same energy level. So, cant allow degeneracy. This creates pressure which counters inwards gravitational pull. Beyond certain mass limit, pressure is not enough and star collapses on itself and cant be a stable white dwarf, hence the limit.<XDE>
Solar system formed 4.6 bn years ago
<XDS>
Sun: 99.86% of solar system mass, 3/4th of it is hydrogen by mass, has layers Core, Radiative zone, Tachocline(transition layer), Convective zone, photosphere(visible surface of sun)
Sun's atmosphere is hotter than the surface, has 3 layers--chromosphere(colored), transition zone, corona(hottest layer)
Beyond this is heliosphere(where solar winds flow), extending beyond Neptune and protecting planets from interstellar medium
Inner/terrestrial/earth-like planets: mercury, venus, earth, mars
Inferior planets: closer to sun than earth=mercury, venus and others/farther are superior planets
Asteroids: largest is Ceres
Outer/jovian/jupiter-like: Gas giants-- Jupiter, Saturn, Ice giants-- Uranus, Neptune
Kuiper belt: a circumstellar orbit beyond Neptune's orbit(30AU) to ~55AU from sun, has 3 officially recognized dwarf planets--Pluto, Haumea, Makemake
Oort cloud: much more on the outside is the inner Oort cloud disc shaped AKA Hills cloud and further is outer Oort cloud, spherical upto 1,00,000 AU
More on planets:
IAU 2006 definition of planet: 3 criteria--1.orbits around sun, 2.mass enough to assume round shape, 3.has cleared its neighbourhood(stuff in its orbit)
If only 1,2 satisfied then it is a dwarf planet like Pluto
Mercury: named after Roman deity Mercury, messenger to gods and NASA had sent MESSENGER to it(launched 2004, ran out of fuel in 2015)
Venus: hottest planet, named after Roman goddess of love and beauty, earth's sister planet, 96% CO2 in atmosphere, highly reflective sulfuric acid clouds make atmosphere opaque, Magellan orbiter 1991
Mars: Roman god of war, has 2 moons Phobos(fear, hence phobia), Deimos(terror), MAVEN and MOM are orbiting it, on surface we have Opportunity rover and Curiosity
Jupiter: largest, named after Roman god of sky and thunder, eq to Greek Zeus, 67 moons, 4 large Galilean moons--Io, Europa, Ganymede, Callisto named after lovers of Zeus
Saturn: Roman god of agriculture, 62 moons, largest moon Titan(brothers/sisters of Greek equivalent god Cronus), Cassini-Huygens space probe
Uranus: only planet named after Greek god(of sky), apart from hydrogen and helium in atmosphere has "ices"--water, ammonia, methane, trace hydrocarbons, 27 moons largest is Titania
Neptune--Roman god of sea, 14 moons largest is Triton(has retrograde orbit), Voyager 2 is only spacecraft to visit it
All planets revolve in same direction around sun in anti-clockwise orbit. Also all planets rotate in same direction as sun (prograde) except. venus that rotates in reverse direction(retrograde) on its own axis, while Uranus has an axis almost horizontal(tilted by 90deg)
<XDE>
13.7BYA big bang, 5-6 BYA stars formed, 5-5.6BYA solar system formed, 4.6BYA planets formed, 4.44BYA moon formed, 4BYA oceans formed on earth, 3.8BYA life began, 2.5-3 BYA photosynthesis got evolved, 2BYA oxygen began to flood atmosphere
On time scale: Eons>Era>Period>Epoch>Age/years
currently we are in Cainozoic era, Quaternary period, Holocene epoch
Evolution of earth
--of lithosphere: process of differentiation(cooling, density change, material moves, layer formation)
--3 stages of atmosphere, hydrosphere: 1.loss of primordial atmosphere due to solar winds, 2. degassing--interior gas released, 3.photosynthesis
Chapter 3 Interior of Earth
Sources of information:
Direct: rocks from mining, deep drilling, volcanic eruptions
Indirect: PVT(pressure, volume/density, temperature) estimates at different depths, gravitation, magnetic field and seismic activity studies
Earthquake: source point=focus=hypocentre, closest point on surface to focus=epicenter
Types of earthquake waves
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