A cone and sphere have equal radii r and equal volumes.
Volume of sphere: Vsphere=34πr3
Volume of cone: Vcone=31πr2h
where h is the height of the cone.
Since the volumes are equal:
34πr3=31πr2h
4πr3=πr2h
4r3=r2h
4r=h
The height of the cone is 4r.
The diameter of the sphere is 2r.
The height of the cone is 4r.
Ratio of diameter to height:
4r2r=21
Therefore, the ratio of the diameter of the sphere to the height of the cone is 1:2.