pendulum. pendulum, a mass, called a bob, suspended from a fixed point so that it can swing in an arc determined by its momentum and the force of gravity. The length of a pendulum is the distance from the point of suspension to the center of gravity of the bob (see center of mass). Share | Cite. where T is the period, or time for one complete swing, l is the length, g is the acceleration of gravity (see gravitation), and Ï = 3.14ââ¦ (see harmonic motion). In 1673, Huygens devised a practicable means of making a pendulum control the speed with which a clock mechanism runs.
We could argue that the first computer was the abacus or its descendant, the slide rule, invented by William Oughtred in 1622. But the first computer resembling today's modern machines was the Analytical Engine, a device conceived and designed by British mathematician Charles Babbage between 1833 and 1871.
At first, these were purely mechanical, but by the start of the twentieth century, they were run by steam.     The first of the modern computers was invented during World War II, in 1941 by a German engineer named Konrad Zuse.The computer was called the Z3 and was used to help design German airplanes and missles. Still others will say the abacus is the first computer. They were  invented by the Chinese between 2600 BC and 300 BC is considered as  the first computer ever. Abacus was used by the merchants and  Clerks in China.