The Birth of Instantaneous Velocity

The Greeks could only handle accelerated or decelerated motion indirectly. The introduction of a quantitative concept of instantaneous velocity was a major step forward. This required a fresh start. A crucial role was played by the so-called Oxford calculators in the fourteenth century. They did prove the Merton-theoremMerton-theorem: In the case of uniform acceleration the motion is, as for the distance covered, equivalent to a uniform motion over the same period with the ‘medial velocity’. This medial velocity is an instantaneous velocity. Soon CasaliCasaliGiovanni and OresmeOresmeNicole represented the results by means of geometrical graphs and instantaneous velocity had become a quantity.