volume & capacity of cylindrical glass The teacher will come with carry a glass and circular plate. He want to explain the capacity of glass.Then we measure diameter with the help of ruler.R=D/2,If D=8cm then R=8/2= 4cm. Without height we can't calculate the volume of a glass. With the help of ruler we measure the height of glass. H=7cm. Volume of a cylindrical glass =pie*r^2h,22/7*4*4*7=352cm^3.(value of pie=22/7 or 3.14)