The Method of Mechanical Theorems convenient to use a little bit of coordinate geometry. If a sphere of radius 1 is placed with its center at "x" = 1, the vertical cross sectional radius formula_2 at any "x" between 0 and 2 is given by the following formula: The mass of this cross section, for purposes of balancing on a lever, is proportional to the area: Archimedes then considered rotating the triangular region between "y" = 0 and "y" = "x" and "x" = "2" on the "x"-"y" plane around the "x"-axis, to form a cone. The cross section of this cone is a circle
Ruhrstahl X-4 aircrew. A massive development effort resulted in a number of heavy-calibre autocannon designs, air-to-air rockets, SAMs, and the X-4. Work on the X-4 began in June 1943, by Dr Max Kramer at Ruhrstahl. The idea was to build a missile with enough range to allow it to be fired from outside the range of the bombers' guns (what is now called a stand-off weapon), while being guided with enough accuracy to guarantee a "kill". The X-4 met these specifications and more; its BMW 109-448 rocket motor accelerated the missile to over 1,150 km/h (715 mph) - about the same speed