Class Notes NCERT Solutions for CBSE Students
Question: How does large variations between day and night temperatures causes weathering?
Answer: How does large variations between day and night, for example – In North India also causes weathering. The rocks expand during the day and contract during the night. Due to expansion and contraction this weakens the rocks and they crack and crumble.
Question: Distinguish between clay, silt and sand.
Answer: Distinguish between clay, silt and sand:
Question: Why is earthworm referred to as farmers friend?
Answer: Earthworms are called farmers friend. They improve the texture of the soil. By burrowing into the soil, they make it loose thus allowing air to enter into it and water to drain from it. They also forms channels in soil for roots to spread through.
Question: How is humus formed?
Answer: The dead plants and animals present in the soil get decayed by the action of bacteria and other microorganisms to form humus.
Question:Give difference between sandy soil and loamy soil.
Answer: The difference is as follows:
