Question

hy is it easier to walk on the sand with shoes with flat base rather than the shoes with sharp heels?

Answer 1

this is because surface area of flat shoe is more than the sharp heel

Answer 2

Sand being rough has less friction (the ability which keeps us constant on the ground) and if we will wear flats so we would be able to balance ourselves better and if we will wear heals so it will cover less area and thus the friction will be less and we will tend to fall.