GEOGRAPHY OF EARTH
• Longitude is measured from East to West
• Latitude is measured from North to
South of Equator.
• New Zealand is close to Int: Date Line.
• Arabia is the larges peninsula.
• Antarctica is in South Pole.
• The largest latitude circle on earth
is the Equator.
• Equinox (equal nights) means the
equal duration of day & night.
• Lines drawn parallel to equator is latitude
• 1 hour difference in local time
between two places is 15 deg: Longitude
• 23 degree longitude is Tropic of
Cancer
• 70% of earth’s surface is covered
with water
• Isobar is the lines joining places of
equal air pressure on a map
• Isohyets are lines joining places of
equal rainfall over a period
• Isotherm are Lines of equal temperature
• Contours are places with equal altitude
• There are 36 tectonic plates
• Crust of earth is 0.5%
• Upper part of earth on which earth
floats is Asthensosphere
• Earth’s speed is greatest when it is
closest to the sun
• Spring tide occurs when earth, moon
and sun are in straight line
• Isthmus is a narrow land strip
separating two seas and connecting two land
marks
• Day and night are equal on 21st March
(at all parallel of latitude) and 23rd September
• Core of earth is metallic
• Temperature at earth’s core is 2000
deg: C
• Tide at its maximum height is spring
tide
• International dateline lies along 180
deg: meridian
• Speed of earth rotation is highest at
the north pole
• Minimum land area recommended for
forest is 25%
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• Earth’s total surface covered by
forests is 15%
• Ordovician are the oldest rock
• Earthquake is a post volcanic activity
• Of total water on earth, fresh water
reserves are 2.7%
• Highest grade of coal is Anthracite
• Coal mainly suitable for thermal
power production is Bituminous
• First stage of coal formation is Peat
• Equator is called the great circle
• Mean radius of earth is 6400 km
• Total world surface area is 510
million sq: km
• soil formed by deposition of silt is
Alluvial soil
• Winds blow from areas of high
pressure to low pressure.
• Movement of tectonic plates may cause
eruption of a volcano
• What creates new islands in the
ocean? Volcanoes
• soil best suited for deep rooted crops
is Black soil
• latitude of south pole is 90 deg:,
latitude of equator is 0 deg:
• humidity in air is maximum in Monsoon
• earth revolves in its orbit 1 deg:
per day
• 1 deg: longitude on equator is equal
to 112 km
• Doldrums is a belt of low atmospheric
pressure on either side of Equator
• Removal of rock layer by layer due to
weathering is called Exfoliation
• Rocks formed by the solidification of
lava are Basalts
• Tundra region gets no rainfall
throughout the year
• At equator an object weights the least.
• At 7050 km per hour, Sun rotate on
its axis.
• The northern polar lights are called
Aurorae Borealis, and southern polar lights are called Aurorae Australis.
• The pulsating universe theory
explains the evolution of universe.
• 230 million years ago there was only
one huge continent on earth. This super continent is known as Panagea, which
means all lands
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• In 1912 Alfred Wegener said that
continents drift around on earth’s surface
• Continental drift means plate tectonics
• Rain forests grow near the equator.
• In autumn deciduous forests glow with
brilliant red and gold colors as the leaves dry up and fall off the trees.
• The shape of the earth is an oblate spheroid.
• Arctic is the worlds northmost region.
• The largest latitude circle on earth
is Equator.
• 230 million years ago, there was only
one huge continent on Earth. This super continent is known as panagea, which
means all lands.
• In 1912, a German Scientist called
Alfred Wegener (1880-1930) suggested that the continent drift around on Earth’s surface.
• The latitude of a point on the
Earth’s surface is the angular distance of that point measured at the centre of
the Earth
• Mass of earth is 6 X 10²¹ tons
• Density of earth is 5.52.
• Chemically earth id made up of Oxygen
46.6%, Silicon 27.7%, Aluminum 8.1%, iron 5%, Calcium 3.6%
• Earth is divided into four zones.
• Torrid zone lies b/w Tropics of
Cancer & Capricorn.
• Torrid zone lies between the Tropics
and is bisected by the Equator
• The North Temperate Zone lies b/w
Tropic of Cancer & the Arctic Circle.
• The South Temperate Zone lies b/w
Capricorn & Antarctic Circle.
• The area around north and south poles
within the polar circles is called ‘the frigid
zone’.
• Hot belt lies b/w latitude 0° & 3°
• Tundra region is a region of high
altitude and is without trees.
• Steppes is the vast, treeless waste
of Russia and part of Asia.
• Moorland is rocky surface.
• Coniferous forests extend up to
13,000 km across North America, Europe &
Asia.
• Tropical or Savannah region lies b/w
desert & forest. More than 1/3rd of Africa is Savannah.
• Pakistan lies in Monsoon land area.
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• The three abundant elements in the
earth’s crust are aluminium, oxygen and silicon. The correct order of their
abundance is silicon, oxygen, aluminum (8.1%)
• Inner core is made mostly of iron.
• Meridian is an imaginary circle in
sky passing though celestial poles.
• Africa is the 2nd largest continent
of the world.
• A wind which reverses seasonally is
known as Monsoon wind.
• Temperature increases with increasing
altitude by 10° C for every 250 meter rise.
• Water vapour turns into clouds in the
atmosphere when Dew Point is reached.
• When a warm air is lifted off the
surface in temperature depression it is called an Occlusion.
• Afternoon rains in the equatorial
region are the result of convectional forces.
• Mediterranean regions are not useful
for forestry.
• The best projection to suit the map
of Pakistan is conventional.
• The extinct Volcano Peak of
Koh-i-Sultan is in Pakistan.
• Cotopaxi: is the highest volcano in
the world. It is situat¬ed in Ecuador.
• Dust Devil: is a dusty whirlwind
normally a few feet in diameter and about 100 feet tall, sometimes also wider
and higher.
• Earth mass: The mass of the earth is
about 81 times that of the moon.
• Earth’s core: is mainly composed of
iron and nickel. Lithosphere is the innermost layer of the earth.
• El Nino: is the weather phenomenon
brewing in the tropical Pacific Ocean. It is the largest climate event of the 20th century setting off
more global disasters than ever before. El Nino is warming of the waters off
Equatorial South America which causes climate abnor¬malities around the world.
The impact can be flooding drought in California, Brazil, Africa and Australia,
severe storms in the Central Pacific and a decline in hurricanes hitting the
south-eastern United States.
• Exfoliation: This type of weathering
is common both in the cold as well as in the hot cli¬mate regions.
• Great
Circle: A circle on the earth’s surface whose plane passes through its centre,
and bisects it into two hemispheres. Two opposing meridians together form a
Great Circle. The shortest distance between any two points on the earth’s surface
is the arc of the Great Circle which passes through
them. 0° latitude
forms a Great Circle. (The
latitude or longi¬tude 75°W should be combined with 75°E to obtain the Great Circle).
• Horse
Latitudes: Sub-trop¬ical belts of high atmospheric pressure over the oceans
situat¬ed in both hemispheres. These are called Belts of Calm between regions
of the Trade Winds and Westerlies of higher latitudes.
• Hydroponics: means culti¬vation of
the plants without use of soil.
• Hyetology: is the study of rainfall.
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• Kandla: is a sea port situat¬ed at
the head of the Gulf of Kuch in Gujarat State.
• Lapse Rate: is the rate of change in
temperature with increase of altitude.
• Laterite soils: Laterite soils are
formed by the weathering of laterite rocks. These can be dis¬tinguished from
other soils by their acidity.
• Loams (loamy soil): Amix¬ture of
sand, clay and silt is known as loamy soil. Loams are formed where the soils have equal proportion of
sand, silt and clay.
• Local winds and their areas:
Khamsin—Egypt; Zonda—Argentina; Santa Ana—California; Simoon— Iran.
• Mansarover Lake: is in Tibet. Near
it, the rivers having their source are the Brahamputra, the Sutlej and the
Indus.
• Maoris (Tribes): are the original
inhabitants of New Zealand.
• Nutrification: is the process of
conversion by action of bacteria, of nitrates in the soil.
• Pangong Tso: is one of the world’s
highest and brackish lakes in Jammu & Kashmir.
• Proxima Centauri: is a star nearest
to the earth.
• Roaring Forties: are west¬erly winds.
• Selvas: The rain forest of Amazon
basin is called Selvas. These are rainy tropical forests.
• Spring Tides: are caused when the sun
and the moon are in a straight line. The tide on its maximum height is known as
Spring Tide.
• Tsunamis: are huge sea waves caused
by earthquakes.
• Willy Willy: is a tropical cyclone of
the north-west Australia.
FACTS OF EARTH
• Largest element found in earth crust
is Silicon, second is Aluminum
• Polar diameter of earth is 7900 miles
• Equatorial diameter is 7927 miles =
12,756 km
• Earth’s polar diameter is shorter
than the equatorial diameter by 43 km
• Distance of equator from either of
poles is 10,002 km
• World is divided into 24 time zones
• Age of earth is 5 billion years
• Speed of earth in orbit around sun is
8.5 miles/sec = 1600 km/min = 29 km/sec
• Weight of earth is 6586 x 10 raise to
18 tons
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• Earth has 46.6% oxygen and 27.7% silicon
• On 21st June, sun is vertically
overhead the Tropic of Cancer
• The South Temperate zone lies between
Capricorn and Antarctic circle
• At equator the duration of the day is
12 hours
• 510 million square kilometers is the
total surface area of the earth
• Sun is 400 times larger than the Moon.
• About 6 billion people living on the Earth.
• When are you most likely to see a
penumbra: During an Eclipse
• At equator an object weights the least.
• A wind which reverses seasonally is Monsoon.
• Water is the most powerful source of erosion
• Tropic of cancer crosses Pakistan.
• Spring tides occur at new moon or at
full moon.
• Neap tides occur at first and third
quarters of the moon.
• Oceans are on average 4 km deep.
• Frozen water covers about 10% of the earth
• Solar eclipse occurs on new moon.
• Lunar eclipse occurs on full moon.
• The standard time of England is known
as Greenwich Mean Time. T is local time of
Greenwich Observatory which on 0° longitude.
• Daylight saving time begun during WWI.
• There are three belts of calm viz:
Doldrums, Tropic of Cancer & Tropic of Capricorn.
• Horn of Africa is Ethiopia, Djibouti
and Somalia.
• Kimberley is associated with Diamonds.
• In Titusfills in Pennsylvania (US) is
world’s first oil-well drilled.
• Thickness of earth crust 20 miles.
• Max height of cloud 20,000.
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ATMOSPHERE OF EARTH
• Nitrogen gas found in atmosphere is
78%, oxygen is 21%
• Speed of electromagnet ways is 300000
km/sec
• The layer of earth in which we live
is Troposphere
• The atmospheric layer closet to earth
is Troposphere.
• Weather phenomenon take place in Troposphere
• Atmospheric layer ideal for flying is Troposphere
• Ionosphere reflects radio-waves back
to earth
• Nimbostratus clouds bring a long
steady rain
• Clouds found at highest altitude are Noctilucent
• Thickness of atmosphere around earth
is 145 km
• Atmosphere maintains earth’s temperature
• % of insulation received by earth’s
surface is 51%
• Atmospheric layers are divided into 4 parts
• Sun’s heat and energy reaches earth
by Radiation
• Air is composed of 78% Nitrogen.
• 21%
Oxygen.
• 1% Other gases.
• Planetary winds consist of doldrums,
trace winds and westerlies.
• Troposphere is 10 km, Stratosphere is
from 10 to 40 km, Mesosphere (Neutraspace) is from 40 to 80 km, Thermosphere (Ionosphere) is from 80 to 370 km and Exosphere
(Heaviside) is beyond 370 km.
• Megnetosphere that lies beyond the
Exosphere is not the part of atmosphere.
• 3/4th of the air that envelops the
earth is in troposphere.
• 97% of the air is below the upper
boundary of the stratosphere which is the maximum height that aircraft may reach with the support of air.
• Smog is when water vapour condenses
around a particle of smoke
• Atmospheric temperature increases at
higher altitudes due to convection
• Formaula of Ozone is O3
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• CFCs are Chloro Fluoro Carbons
• Earth’s atmosphere is over 1000 km deep
• Biosphere is the sphere of life which
covers all the three spheres i.e litho, hydro,
atmosphere
• Ozone layer is found in Stratosphere.
• Climate is the average weather of a
particular place over many years. Weather change day to day, whereas climate
remains same for years.
• Every seson, trees add a new ring of
growth to their trunks
• Clouds are made of water droplets,
ice, crystals, particles of dust and air
• Warm air can hold more water vapour
than cold air
• The age
of Earth is calculated as 4500 million years.
• Ozone is measured in percentage (chk)
• The amount of ozone in the atmosphere
is expressed in ppm/ The amount of ozone in the atmosphere is expressed in dobson units (chk)
• Air is composed of nitrogen
(78.08%),oxygen (20.95%),argon (0.94%) and carbon dioxide (0.03%).
• Nitrogen gas dominates the earth’s surface.
• Weathering takes place more quickly
in warm, wet area than in cold and dry regions.
• An atmosphere is a blanket of gas
that surrounds a plane. Earth’s atmosphere is over 1000 kilometers deep, but
most of it is in the 30 kilometers closest to
Earth.
• Weight of the air pushing on us is
known as atmospheric pressure.
• Atmospheric pressure is equal to
14.73 lbs per sq. inch.
• Atmospheric pressure decreases with height.
• In nature the nitrogen of the
atmosphere is made available for the plant growth through the activity of bacteria called nitrogen fixation of
bacteria in roots of plants. Earthworms provide nitrogenous wastes.
• Ozone is found in stratosphere b/w 20
to 50 km.
• The
tidal effect of Moon on the surface
of Earth is less that that of
Sun because Moon’s gravitational
pull at Earth’s surface is less as compared to Sun’s gravitational pull. Tidal effect of sun is 146% of moon.
• Injurious ultraviolet radiations are
mostly prevented from reaching the earth as these are absorbed mostly by Ionosphere.
• 510 million square kilometers is the
total surface area of the earth.
• At 7050 km per hour, Sun rotate on
its axis.
• The northern polar lights are called
Aurorae Borealis, and southern polar lights are called Aurorae Australis.
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•
The pulsating universe theory explains the evolution of universe.
The gluteus
maximus is the largest muscle in the body and it is often called the strongest
muscle in the body because it is the primary muscle that keeps the body erect
during walking. If a person's glueteus maximus is injured, he or she will often
end up walking in a slouched or slumped posture. Conversely there are the
muscles of the eye, which are some of the smallest muscles of the body. Despite
their size, they are often considered to be some of the strongest muscles in
the body because of strength endurance and elastic strength properties, which
allows them to exert force quickly. The eye muscle's dynamic strength,
basically the ability to complete repeated motions, is also very strong. The
external muscles of the eye are constantly at work, moving the eyes at a nearly
nonstop pace during the day.
Only women have
the muscles of the uterus, another group of muscles that, when combined, are
sometimes called the strongest muscle in the body. These muscles are used during
birth, and are responsible for pushing the baby out through the birth canal.
The amount of absolute strength and elastic strength generated by these muscles
is incredible, but they are not used that often.
A muscle that is
used often is the heart, which has greater strength endurance than any other
muscle in the body. The heart is often considered to be the strongest muscle in
the body because it is the hardest working muscle in the body. The heart never
stops working from birth until death, pumping approximately 2 billion times
during a person's lifetime.
Source: What Is The Strongest
Muscle In The Body
What is the
strongest human muscle? Is it your biceps, quadriceps or could it be your
gluteus maximus? You might be surprised to learn that it’s none of the above.
Though it depends on what your definition of “strongest” means.
If you by
strongest you mean “ability to exert a force on an external object”, then a
human’s strongest muscle is his or her ‘masseter’ muscle. The masseter muscle
is a thick muscle in the cheek and is located at the back of the jaw. It’s
responsible for opening and closing your jaw during chewing. It is the muscle
that can generate the largest externally measurable force attributable to the
action of a specific muscle. Its strength is the result of incredibly densely
packed muscle fibers combined with being attached to a short-armed lever. It
can close the teeth with a force as great as 55 pounds (25 kilograms) on the
incisors or 200 pounds (91 kilograms) on the molars. Guinness Book of Records
lists the strongest bite recorded at 975 lb for 2 seconds. That’s more than six
times the normal biting strength of a human.
Now if you take
‘strongest’ to mean ‘does the most work’, the heart lies claim to that. The
heart performs the largest amount of physical work in the course of a human’s
life. The power output of the human heart range is estimated to be between 1 to
5 watts. Compared to the power output of other muscles, it’s much less. For
example, the quadriceps can produce over 100 watts, but only for a few minutes,
then it fatigues. The heart does its work continuously over an entire lifetime
without pause, and hence ‘outworks’ every other muscle.