Question

question 4
which of the following factors does not exert pressure on rocks that leads to physical weathering?
○ carbonic acid
○ plant roots
○ overlying rocks
○ freezing water

Explanation:

To determine which factor does not exert pressure for physical weathering, we analyze each option:

• Plant roots: As roots grow, they exert pressure on rocks, causing physical weathering.
• Overlying rocks: The weight of overlying rocks exerts pressure on underlying rocks, leading to physical weathering (e.g., exfoliation due to pressure release).
• Freezing water: When water freezes in rock cracks, it expands, exerting pressure that breaks rocks (physical weathering).
• Carbonic acid: Carbonic acid causes chemical weathering (e.g., dissolving minerals like calcite in limestone), not physical weathering through pressure. It involves chemical reactions, not mechanical pressure.

Answer:

A. carbonic acid