Which of the following is NOT a Direct source for obtaining information about the interior of earth?
Explanation: This and many deep drilling projects have provided large volume of information through the analysis of materials collected at different depths. Volcanic eruption forms another source of obtaining direct information. As and when the molten material (magma) is thrown onto the surface of the earth, during volcanic eruption it becomes available for laboratory analysis. However, it is difficult to ascertain the depth of the source of such magma. Analysis of properties of matter indirectly provides information about the interior. We know through the mining activity that temperature and pressure increase with the increasing distance from the surface towards the interior in deeper depths. Moreover, it is also known that the density of the material also increases with depth. It is possible to find the rate of change of these characteristics. Knowing the total thickness of the earth, scientists have estimated the values of temperature, pressure and the density of materials at different depths. The details of these characteristics with reference to each layer of the interior are discussed later in this chapter.
Consider the following statements:
Which of the above statement(s) is/ are correct?
Explanation: All natural earthquakes take place in the lithosphere. Earthquake waves are basically of two types — body waves and surface waves. Body waves are generated due to the release of energy at the focus and move in all directions travelling through the body of the earth.
Which of the following statements is correct?
The earthquake events are scaled either according to the magnitude or intensity of the shock. The magnitude scale is known as the Richter scale. The magnitude relates to the energy released during the quake. The magnitude is expressed in absolute numbers, 0-10. The intensity scale is named after Mercalli, an Italian seismologist. The intensity scale takes into account the visible damage caused by the event. The range of intensity scale is from 1-12.
Which types of volcanic eruptions have caused Deccan Trap formations?
Explanation: The Deccan Traps from India, presently covering most of the Maharashtra plateau, are a much larger flood basalt province.
Which of the following statements about ‘Tillite’ is correct?
Explanation: Tillite is the sedimentary rock formed out of deposits of glaciers. The glacial tillite provides unambiguous evidence of palaeo-climates and also of drifting of continents.
Which of the following statements is/are correct?
Explanation: The average temperature of surface water of the oceans is about 27°C and it gradually decreases from the equator towards the poles. The rate of decrease of temperature with increasing latitude is generally 0.5°C per latitude.
The height of a wave is determined by its ____
Explanation: A wave’s size and shape reveal its origin. Steep waves are fairly young ones and are probably formed by local wind. Slow and steady waves originate from faraway places, possibly from another hemisphere. The maximum wave height is determined by the strength of the wind, i.e. how long it blows and the area over which it blows in a single direction.
According to Wegner which of the following forces were responsible for the drifting of the continents?
Explanation: Wegener suggested that the movement responsible for the drifting of the continents was caused by pole-fleeing force and tidal force. The polar-fleeing force relates to the rotation of the earth. You are aware of the fact that the earth is not a perfect sphere; it has a bulge at the equator. This bulge is due to the rotation of the earth. The second force that was suggested by Wegener—the tidal force—is due to the attraction of the moon and the sun that develops tides in oceanic waters.
Which one of the following is the type of plate boundary of the Indian plate along the Himalayan mountains?
Explanation: The Indian plate includes Peninsular India and the Australian continental portions. The subduction zone along the Himalayas forms the northern plate boundary in the form of continent— continent convergence.
Which of the following statements is correct?
Explanation: Point bars are also known as meander bars. They are found on the convex side of meanders of large rivers and are sediments deposited in a linear fashion by flowing waters along the bank Meander is not a landform but is only a type of channel pattern. This is because of (i) Propensity of water flowing over very gentle gradients to work laterally on the banks; (ii) unconsolidated nature of alluvial deposits making up the banks with many irregularities which can be used by water exerting pressure laterally; (iii) coriolis force acting on the fluid water deflecting it like it deflects the wind.
Meanders develop over flood and delta plains.
Which of the following is NOT a permanent gas of the atmosphere?
Explanation: Permanent Gases of the Atmosphere
Which of the following statements is NOT correct?
Explanation: Water vapour is also a variable gas in the atmosphere, which decreases with altitude. Water vapour also decreases from the equator towards the poles. It also absorbs parts of the insolation from the sun and preserves the earth’s radiated heat. It thus, acts like a blanket allowing the earth neither to become too cold nor too hot. Water vapour also contributes to the stability and instability in the air.
Choose the correct option:
Assertion (A): The gravitation force (g) is greater near the poles and less at the equator.
Reason(R): This is because of the distance from the centre at the equator being greater than that at the poles.
Explanation: The gravitation force (g) is not the same at different latitudes on the surface. It is greater near the poles and less at the equator. This is because of the distance from the centre at the equator being greater than that at the poles.
Mark the incorrect among the following:
Explanation: The release of energy occurs along a fault. A fault is a sharp break in the crustal rocks. Rocks along a fault tend to move in opposite directions. As the overlying rock strata press them, the friction locks them together. However, their tendency to move apart at some point of time overcomes the friction. As a result, the blocks get deformed and eventually, they slide past one another abruptly. This causes a release of energy, and the energy waves travel in all directions.
The Mohorovicic discontinuity refers to
The Mohorovičić discontinuity ,usually referred to as the Moho, is the boundary between the Earth's crust and the mantle.The Moho lies almost entirely within the lithosphere.
Arrange the following in chronological order
Which of the followings is/are NOT the components of a map?
There are three Components of Maps – distance, direction and symbol.
What is not true about Feldspar?
Explanation: Feldspar: Silicon and oxygen are common elements in all types of feldspar and sodium, potassium, calcium, aluminium etc. are found in specific feldspar variety. Half of the earth’s crust is composed of feldspar. It has light cream to salmon pink colour. It is used in ceramics and glass making.
The direction of wind around a low pressure in northern hemisphere is:
If a low-pressure area forms in the atmosphere, air flows towards this region, but will be deflected perpendicular to its velocity by the Coriolis force. Instead of flowing straight towards the low pressure area, the air ends up circulating around it.
This pattern of air flow is called a cyclone. In the Northern Hemisphere the direction of rotation around a low pressure area is counter-clockwise or anti-clockwise.
Consider the following statements about jet Stream circulations choose the correct ones:
Choose the correct answer—
Explanation: Jet streams are stronger in winter than in summer because arctic and tropical air masses create a stronger surface temperature contrast in winter causing a stronger jet stream but in summer surface temperature variation is less dramatic.
A meridian is
A (geographic) meridian (or line of longitude) is the half of an imaginary great circle on the Earth's surface, terminated by the North Pole and the South Pole, connecting points of equal longitude, as measured in angular degrees east or west of the Prime Meridian.
Excluding the moon, the celestial object that generally appears bright in the sky is
Explanation: Venus is the most prominent planet, often called the "morning star" or "evening star" because it is brighter than the stars and visible near sunrise or sunset depending on its location in its orbit. Mercury, Mars, Jupiter and Saturn are also visible to the naked eye.
Lines joining places of equal rainfall are known as
An isohyet or isohyetal line is a line joining points of equal rainfall on a map in a given period . A map with isohyets is called an isohyetal map.
Atoll refers to
Explanation: An atoll is a ring-shaped coral reef, island, or series of islets. An atoll surrounds a body of water called a lagoon. Sometimes, atolls and lagoons protect a central island. Channels between islets connect a lagoon to the Open Ocean or sea.
What does 'Roaring forties' refer to?
The region between latitudes 40° and 50°S, where the prevailing westerly winds blow over the open oceans with great regularity and strength
The Roaring Forties are strong westerly winds found in the Southern Hemisphere, generally between the latitudes of 40 and 50 degrees. The strong west-to-east air currents are caused by the combination of air being displaced from the Equator towards the South Pole, the Earth's rotation, and the scarcity of landmasses to serve as windbreaks.