If the surface area of the cone is 15 π and the center angle of the side view is 60 °, then the volume of the cone is 15 π___ .

If the surface area of the cone is 15 π and the center angle of the side view is 60 °, then the volume of the cone is 15 π___ .

Let the bottom radius of the cone be r, and the generatrix be l, then 2 π r = 13 π L, we get l = 6R, s = π R2 + π R · 6R = 7 π R2 = 15 π, we get r = 157, the height of the cone H = l2-r2 = 35r, that is, H = 35.157, v = 13 π r2h = 13 π × 157 × 35 × 157 = 2537 π