There is a cross-sectional view as shown in the following figure, which is described in detail as follows: the figure is divided into two parts, the lower part is a cylinder and the upper part is a cylinder.

It is a cone, and there is a spiral line along the surface from the conical part to the cylindrical part. The radius of the cylindrical part is R (constant), the total height of the cone is H (constant) and the pitch is M (where the pitch of the cylindrical part is M0, constant; Conic curve is a variable), and the expression given is dM/dθ= 1/(r*r). Try to find the relationship between H (height) and θ (any point on the helix rotates θ angle, and the height of H rises).