In terms of a deeper scientific reason, I am not sure, but the basic reason is quite simple. "Mud" tends to look like a mix between a solid, dirt, and a liquid, water or some other liquid. Since it is, in fact, a cross between a solid and a liquid, it has properties of both. It has certain physical and visual properties that only a solid would have, such as texture and opaqueness, but it also has physical properties of a liquid. Since it leans more towards the liquid side than the solid side, we say mud "flows" rather than saying that it "rolls" or "bounces".
Answer:
A. Steep hillside, little vegetation, strong downpours
Explanation:
between a steep hill and a flat valley, the hill is more likely to be affected because of gravity. with a valley theres less places for the dirt to actually move to. So C and D are not correct
a lack of vegetation and heavy downpour is the perfect condition for erosion. plants' root system makes dirt and rock more stable. without a lot of roots to hold the dirt in place and absorb water before it runs over the rocks and breaks them down, heavy rain would be a lot more likely to erode the area. so B isnt right either
Answer:
B.
Explanation:
Because the delocalised electrons are free to move.
Metallic bonds are formed by the electrostatic attraction between the positively charged metal ions, which form regular layers, and the negatively charged delocalised electrons. These are the electrons which used to be in the outer shell of the metal atoms. These delocalised electrons are free to move throughout the giant metallic lattice, so as one layer of metal ions slides over another, the electrons can move too keeping the whole structure bonded together.
This is the opposite of what happens in a giant ionic lattice, where both the positive ions and the negative ions are locked in place. If the crystal is stressed and one layer moves with respect to another, the positive ions can end up lined up with each other, and the negative ions lined up with each other. This causes repulsion, so the crystal fractures.