How come ripples form on the top layer of sand???

Question

...tom science

Answer 1

Not so fast, it can be from either wind or water. Either way, under the right conditions, whatever is moving the particle of sand can form an eddy current behind an obstruction and deposit the particle a given distance (depends on velocity and weight of the particle) behind the obstruction--which forms another obstruction--which forms another eddy current......

But ripples are not always formed--if the grains of sand are too fine, or the velocity too high, you'll get a smooth surface.

Answer 2

For much the same reason that waves form on the top layer of water; currents of air travel across the surface of the sand, picking up particles and depositing them elsewhere. Depending on the exact geometry of each individual grain of sand, some stick to their surrounding grains or have a low enough profile that they do not get picked up, and instead form a surface where other grains can get stuck, temporarily. As time passes, some of these raised areas form tiny little drifts in the sand where there is less motion than the areas adjacent to them.

Answer 3

from the wind blowing across the surface of the sand.

Answer 4

Wind.

Answer 5

It is caused my the wave action.