Gravity acts alone to produce avalanches and landslides. When the force of gravity exceeds the strength of the material holding it in place on a slope, the material will move downhill in the form of an avalanche or landslide.
Wind is the erosional force that forms sand dunes.
wind
Wind
The force of winds shapes sand dunes.
The force is gravity.
wind is an agent of erosion which causes sheet erosion
The force of an avalanche primarily comes from gravity pulling the snow downhill. Factors like the steepness of the slope, the amount of snow, and the presence of weak layers within the snowpack can also contribute to the force of an avalanche.
Gravity is the key force pulling an avalanche downhill. As snow accumulates on a slope, it can reach a critical point where the force of gravity overcomes the friction between layers of snow, causing the avalanche to slide downhill.
i think water erosion created norways fjords
It is called aeolian erosion
Sand dunes are formed by wind, which is one kind of erosion.