A granular substance such as sand naturally settles in to a cone shaped pile when poured from a small aperture it?s height depends on the humidity and adhesion between granules the angle of elevatio. A granular substance such as sand naturally settles in to a cone shaped pile when poured from a small aperture it?s height depends on the humidity and adhesion between granules the angle of elevation of a pile is called the angle of repose if the height of a pile of sand is 15 ft and it?s diameter is approximately 52 feet determine the angle of repose