Question

it is difficult to walk on sandy surface. why

Answer 1

This is because sand yields under the weight of the person walking on it. This difficulty can be overcome by placing a wooden plank on the sand. Then the weight of the man will act on larger area and hence pressure exerted on sand decreases. Therefore it is difficult to walk on sand.
hope it helps you

Answer 2

When we walk on the sand we push the sand with our feet but the sand yields i.e., it does not react back with the same force. That is why it is difficult to walk on the sandy surface.


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