Question

I can't walk on sand give reason

Answer 1

we can't walk on sand properly because the friction is decreased

Answer 2

u can't walk on sand because it slides around under your foot pressure.The sand is not like a rigid body i.e. it gives way when pressure is applied to it. As we walk on sand. the sand sifts under our feet and moves down as we walk making it difficult for us to walk on sand as its not a stable surface.

hope it helps