Class 9 Shaping of the Earth's Surface Mock Test (CBSE)

Topics in Shaping of the Earth's Surface

• Plate tectonics
• Weathering
• Erosion
• Running water: waterfalls, meanders, deltas
• Waves and currents
• Glaciers
• Wind
• Underground water
• Landslides and avalanches
• Glacial lake outburst floods
• Dust storms

Shaping of the Earth's Surface practice questions with answers

1. Q1Multiple choice·1 mark
   Which of the following is a primary trigger for sudden landslides and avalanches in mountainous regions?

   1. (a)Thick forest cover on the mountain slopes
   2. (b)Heavy rainfall or seismic activity
   3. (c)Slow chemical weathering of the rocks
   4. (d)Gradual creep of soil down the slope
   Show answer and step marks

   1. Correct option: (b) Heavy rainfall or seismic activity+1

   Answer: (b)
2. Q2Multiple choice·1 mark
   What is the primary cause of a Glacial Lake Outburst Flood (GLOF)?

   1. (a)Complete melting of underground water tables
   2. (b)Sudden breach of a natural moraine dam holding a glacial lake
   3. (c)Gradual formation of river meanders
   4. (d)Continuous deposition of wind-borne sand
   Show answer and step marks

   1. Correct option: (b) Sudden breach of a natural moraine dam holding a glacial lake+1

   Answer: (b)
3. Q3Short answer·3 marks
   Define weathering. Explain any two types of weathering that play a crucial role in shaping the Earth's surface.
   Show answer and step marks

   1. Definition: Weathering is the breaking down or disintegration of rocks and minerals on the Earth's surface in-situ by agents like water, temperature changes, and biological activity.+1
   2. First type, any one of: physical (mechanical) weathering, in which temperature changes or freeze-thaw break rocks into pieces without changing their composition; chemical weathering, in which reactions such as oxidation, carbonation or hydrolysis decompose rocks and alter their minerals; biological weathering, in which plant roots and burrowing animals break rocks apart; or any other valid type.+1
   3. Second type, a different one from the same list.+1

   Answer: Weathering is the in-situ breakdown of rocks on the Earth's surface by agents such as temperature changes, water and living things. Any two of: physical weathering (rocks break up through temperature changes or freeze-thaw, without change in composition); chemical weathering (oxidation, carbonation or hydrolysis alter the minerals); biological weathering (roots and burrowing animals break rocks).

More Class 9 Social Science (SST) mock tests