Explore topic-wise InterviewSolutions in .

The Borra caves near Visakhapatnam in Seemandhra

Thick masses of ice slowly move downhill in snow-clad region are called glaciers.

Erosion:

Limestone caves

Depositions:

• Stalactites
• Stalagmites
• Limestone Pillars

Velocity of the river decreases when it nears the river mouth. Most rivers branch out to distributaries at this stage where the volume of both water and sediments is high. The sediments brought by the river are deposited between these distributaries forming almost triangular-shaped landforms called deltas. These features are called as they resemble the Greek alphabet

A (Delta).

The course of a river can generally be divided into three stages based on the difference in slope from its source to mouth.

• Upper course
• Middle course
• Lower course

Upper course is that part of the river where it rapidly flows down along steep slopes from the place of origin. The intensity of erosion is severe in this course. Middle course is that stage of the river where it flows through gently sloping foothills. As the velocity of the flow decreases, the intensity of erosion declines and deposition begins.

Lower course is the stage where the river flows through the plains. The rate of deposition will be higher due to the slow pace of the river and the increase in the amount of sediments during this stage.

The sand dunes formed in the deserts are as a result of the deposition by wind. The sand dunes commonly formed in crescent shapes are called barchans

The strong whirlwind carry away the dry desert sands from one place to another. This process of wind erosion is called deflation.

Answer is (c) Deserts

1. The velocity at which the agent is moving has a great impact on deposition. 

2. If the stream or wind slows down, the carrying capacity and the particle sizes carried and deposited will decrease. 

3. If a stream flows faster, say during floods or when the river is in the mountains, then the carrying power of the stream and the sizes of particles deposited will increase.

4. If there is a change in the slope of land or in the direction of flow, deposition may occur there. 

5. The slopes are absent in the plain region. Therefore, the rivers are unable to carry the sediments further and they start depositing. 

6. Due to gravity, small particles settle more slowly than the larger particles. Smaller particles are carried away by the river or wind till the end and their deposition occurs in the later stage.

7. If an obstacle comes in between the flow of the agent it causes the particles to settle and thus deposition takes place.

Correct Answer is  (c) Glaciers

There is direct relationship between the velocity of the agents and the process of deposition because-

1. The velocity at which the agent is moving has a great impact on deposition.

2. If the stream or wind slows down, the carrying capacity and the particle sizes carried and deposited will decrease. 

3. If a stream flows faster, say during flo’ods or when the river is in the mountains, then the carrying power of the stream and the sizes of particles deposited will increase. 

4. On the other hand, if there is a change in the slope of land or in the direction of flow, deposition may occur there. 

5. If the slope of a region is almost absent like in plain region, the rivers are unable to carry the sediments further and start depositing.

All the continents and even the oceans are actually situated on a massive base of rocks called ‘plates’.

• In the beginning, probably all continents were held together.
• Later the earth’s lithosphere is broken up into several pieces, just like the pieces of a large jigsaw puzzle and thus continental plates formed. 
• These pieces, on which all the continents and oceans are actually situated, are called “Plates”. 
• They float on soft layer of the mantle. 
• There are about seven major plates and several minor plates on the earth. 
• As the plates move, they push, pull, slide, rise, sink, bend and break. 
• Sometimes one plate meets another, the incoming plate dips under the stable plate. 
• In fact the incoming plate actually goes into the mantle of the earth and becomes molten due to the heat of the mantle. 
• That is how some plates are eventually destroyed.

B) Because the Eurasian plate pushed the Indian plate.

Plates float on the Mantle

Correct option is A) Kerala

(C) 1st order

C) Lava spills from volcanic eruptions

A river, which is flowing water, erodes rock materials, transports them to newer places and deposits them. In this process, it creates many erosional and depositional landforms. Let us study in details about erosional landforms:

George: 

1. In mountainous areas, river flows at a higher speed. 

2. Here, the bed gets more eroded than its banks. Gorges are formed with steep banks and a narrow bed. For example, gorges of river Ulhas and river Narmada. Deeper gorges are called canyons.

V-shaped Valleys: 

1. Over a period of time, the bed of the river is less eroded. 

2. Erosion along the banks and the slope of the valley increases. 

3. The vertical sides of the valley become wide resembling letter V’. These are V-shaped valleys.

Waterfalls: 

When a river runs over alternating layers of hard and soft rock, rapids and waterfalls are formed. Jog falls on the Sharavati river.

Potholes: 

1. They generally originate below waterfalls on where rocks are structurally weak. 

2. Swirling whirlpool motions of the river water causes stones at the bottom to grind the bedrock and enlarge the potholes by drilling while finer sediments are carried away in the current. 

3. Potholes may range from a few centimetres to many meters in diameter and depth. For example, large potholes can be seen in the beds of river Kukadi at Nighoj in Ahmednagar district.

Correct Answer is  (c) Glacier

C) They have continuously been moving for millions of years now.

Deposition starts generally along the side and front of ice.

Loess: The fertile deposits of fine dust beyond the desert limit is called Loess.

Loess is the fine dust bloom beyond the desert limit and is deposited on the neighboring lands.

(B) Hydrosphere

B) At tectonic plate boundaries

(C) Plucking

Fujiyama Volcanic mountain located in Japan.

Correct option is  (b) Headward erosion

Correct Answer is  (c) Moraine

Correct Answer is  (b) Karst

• More than 10,000 tonnes of anti biotics are consumed in Europe each year. 
• 30%-60% of them passthrough animals and humans unchanged and reach the ocean. 
• These antibiotics can affect the marine ecosystems over a long period, with detrimental effects on natural marine communities of bacteria.
• The presence of antibiotics in the marine environment is worrying as it can reach to humans through the consumption of sea food and fish. 
• The marine sediments affected by the antibiotics metabolise both nitrogen and carbon which are linked to both eutrophication and climate problems.

Drumlins, eskers, moraines are the depositional features formed by glaciers.

B) Mountains

B) plate boundaries are found all the way around the Pacific basin.

Loess are yellow in colour.

• Gorges are narrow valleys with steep sides.
• A gorge is almost equal in width at its top as well as its bottom. 
• They are suitable for the construction of massive reservoirs. The natural valleys formed by the gorges are built up with hard rock. 
• The valleys with its steep sides, extensive rocky floors form the natural reservoirs for the dams. 
• Constructing the dams at gorges is less expensive because a little concrete work is needed to form the reservoirs. 
• In these vast and massive reservoirs a lot of water can be stored. 
• Gorges are flood proof. They prevent floods. 
• The waterfalls that falls down from great heights into the gorges can rotate large turbines and generate hydroelectricity in large quantities.
• Thus gorges are suitable for the construction of dams.

(D) the Sunder bans

• The gradual disintegration of rocks is caused by atmosphere forces. 
• The rocks when exposed to heat expand and contract when cooled down. 
• As surface rock contracts and expands and contracts again, it gradually becomes brittle and begins to break down.
• Water reacts with the chemicals in the rock and further weakens it. 
• These processes by which the rocks are weakened and broken are called ‘weathering’. 
• It is easier to chip small pieces of rock from the outer layer rather than from the core of the rock. 
• Thus we can say the rocks are harder inside than outside.

Volcanoes: Volcanoes are places on the earth’s surface where molten material from the mantle erupts onto the Earth’s surface.

Mushroom rock is the erosional form of rock caused by winds

Correct option is  (a) Sea cave

(D) Jammu and Kashmir

The biggest Canyon in the world is on the river Colorado. The Grand Canyon in the USA is 466 km in length. Its depth is 1.6 km and its width is 188m to 29km.

(A) glaciers

As it descends the steep slopes the river flows swiftly exerting a great force, cuts the mountains vertically, and forms V-shaped valleys.

Gorges are suitable for construction of dams.

V – shaped valleys are formed by rivers

Glaciers are most commonly found above snow line i.e., regions of high snow fall in winter and cool temperatures in summer. These conditions allow more snow to accumulate on the glacier in the winter that will melt in the summer. This is why most glaciers are found either in mountainous areas or the polar regions.

We are in the state of Andhra Pradesh. It is a semi-arid area and has a predominantly hot and dry climate. Summers start in March, and peak in May with average high temperatures in the 42°C range. A dry, mild winter starts in late November and lasts until early February with little humidity and average temperatures in the 22°C – 23°C range. In such hot and dry conditions glaciers are not formed. So we cannot find glaciers in our surroundings.

Erosion cycle (or) Geomorphic cycle: A process through which mountains, plateaus, and plains keep on changing is called the Erosion cycle (or) Geomorphic cycle.