(b) A worker wishes to pile sand onto a circular area in his yard. The radius of the circle is R. No sand is to spill onto the surrounding area; see Fig. Show that the greatest volume of sand that can be stored in this manner is mµ,R 3/3 .where us is the coefficient of static friction of sand on sand. (The volume of a cone is Ah/3, where A is the base area and h is the height.)

(b) A worker wishes to pile sand onto a circular area in his yard. The radius of the circle is R. No sand is to spill onto the surrounding area; see Fig. Show that the greatest volume of sand that can be stored in this manner is mµ,R 3/3 .where us is the coefficient of static friction of sand on sand. (The volume of a cone is Ah/3, where A is the base area and h is the height.)