The heaviest rocks, which are rolled along the river bed in river transport, come under which type of load?
- A.Solution load
- B.Suspension load
- C.Saltation load
- D.Traction load
Correct answer
Explanation
The correct answer is D, Traction load. Boulders and large pebbles are too heavy to be lifted by the water, so the river rolls, slides and drags them along its bed; this is traction.
A river carries its load in four ways. Dissolved minerals such as calcium carbonate move invisibly in solution. Fine clay and silt stay floating in the water as suspension, which gives rivers like the Ganga their muddy colour. Sand and small pebbles move in short hops, lifted and dropped again, which is saltation. The heaviest pieces stay on the bed and are rolled or pushed, which is traction. Saltation and traction together are called the bed load. Traction is strongest in fast upper courses and during floods, when the river has the most energy.
A is wrong because solution load is dissolved matter, not rocks. B is wrong because only the finest particles stay suspended. C is wrong because saltation moves medium-sized grains by bouncing, not the heaviest rocks.
Exam tip: from lightest to heaviest: solution, suspension, saltation, traction.
Practice Questions
View allConsider the following statements: 1. River Kaveri has well developed valley 2. Valley of River Alakananda is still growing 3. River Krishna is largest east flowing peninsular river Which of the statements given above is/are correct?
- A.1 only
- B.1 and 2
- C.2 and 3
- D.2 only
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The Kaveri is an old peninsular river with a mature valley, and the Alaknanda is a young Himalayan river still cutting its valley, but the largest east-flowing peninsular river is the Godavari, not the Krishna.
Read the full explanation →Which one of the following statements is NOT correct?
- A.Mahogany is a timber species of Tropical Rainforest
- B.Chaparral vegetation is found in Taiga climate
- C.Lichens are predominantly found in Tundra region
- D.Sal is a representative species of Moist Deciduous Forest
Show answer
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Read the full explanation →In India, Cardamom Hills are regarded as a continuation of the
- A.Eastern Ghats
- B.Mizo Hills
- C.Naga Hills
- D.Western Ghats
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The Cardamom Hills form the southernmost part of the Western Ghats, lying south of the Palghat Gap along the Kerala–Tamil Nadu border.
Read the full explanation →The speakers of major Indian languages belong to how many language families ?
- A.Two
- B.Three
- C.Four
- D.Six
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The major languages of India belong to four language families: Indo-European (Indo-Aryan), Dravidian, Austric (Austro-Asiatic) and Sino-Tibetan. The Indo-Aryan branch of the Indo-European family is the largest, spoken by about three-quarters of Indians and including Hindi, Bengali, Marathi, Gujarati, Punjabi and Odia.
Read the full explanation →Which one of the following features is the result of erosion and deposition work of a river?
- A.Pothole
- B.Oxbow lake
- C.Levee
- D.Rapid
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An oxbow lake forms when a river erodes the outer banks of a meander and deposits silt that seals off the loop, so it needs both erosion and deposition.
Read the full explanation →