In geometry, a spherical sector is a portion of a sphere defined by a conical boundary with apex at the center of the sphere. It can be described as the union of a spherical cap and the cone formed by the center of the sphere and the base of the cap.
If the radius of the sphere is denoted by r and the height of the cap by h, the volume of the spherical sector is
If the radius of the base of the cap is denoted by a, the surface area of the spherical sector is