Volume 2 : 3 ratio of the volumes of the sphere and cylinder is credited to Archimedes. The volume of a sphere is the integral of an infinite number of infinitesimally small circular disks of thickness "dx". The calculation for the volume of a sphere with center 0 and radius "r" is as follows. The surface area of the circular disk is formula_10. The radius of the circular disks, defined such that the x-axis cuts perpendicularly through them, is or where y or z can be taken to represent the radius of a disk at a particular x value. Using y
Northrop X-4 Bantam could be practical. Semi-tailless designs appeared on the X-36, Have Blue, F-117, and Bird of Prey, although these aircraft all differed significantly in shape from the X-4. The trend during its test program was already towards delta and modified delta aircraft such as the Douglas F4D, the Convair F-102A derived from the XF-92A, and the Avro Vulcan. Northrop X-4 Bantam The Northrop X-4 Bantam was a prototype small twinjet aircraft manufactured by Northrop Corporation in 1948. It had no horizontal tail surfaces, depending instead on combined elevator and aileron control surfaces (called elevons) for control in pitch and roll attitudes,