8. Define the following:
Humus
. Cohesion
. Plasticity
Answers
Explanation:
Humus:Humus is dark, organic material that forms in soil when plant and animal matter decays. When plants drop leaves, twigs, and other material to the ground, it piles up. ... The thick brown or black substance that remains after most of the organic litter has decomposed is called humus.
Cohesion:Cohesion of soil is an important factor of soil consistency. ... In soil physics, BA VER (2), for example, defines it as "the cohesive force that takes place between adja- cent particles". On the other hand, in soil mechanics, cohesion means "the shear strength when the compressive stresses are equal to zero".
Plasticity:Plasticity of soil is its ability to undergo deformation without cracking or fracturing. The main engineering properties of soils are permeability, compressibility and shear strength. Permiability indicates facility with which water can flow through soils.
Answer:
Humus are the dark, organic material present on top of the soil. This organic matter mainly constitutes of dead and decaying animal substances, dried leaves, twigs, grasses, vegetables, microbes and other nutrients. Humus are naturally obtained soil, which can be easily produced through a process called composting.
As for the definitions, the tendency of two or more different molecules to bond with each other is known as Adhesion, whereas the force of attraction between the same molecules is known as Cohesion. ...
When solids are bent or beaten into a specific (desired) shape, the permanent changes to the shape of the material as a consequence of its plasticity can be considered as a property of the material itself (since the changes occur within it). ..