One of the earliest known uses of a pendulum was in the 1st. century seismometer device of Han Dynasty Chinese scientist Zhang Heng. Its function was to sway and activate one of a series of levers after being disturbed by the tremor of an earthquake far away. Released by a lever, a small ball would fall out of the urn-shaped device into one of eight metal toad's mouths below, at the eight points of the compass, signifying the direction the earthquake was located.
Nowadays the pendulum can be used to show the Earth spins, to measure the acceleration due to gravity which is important in determining the shape of the earth and the distribution of materials within it.
The oscillation period is given by:
l: string lenght; g: gravity
Experience
Each pendulum has different size of string that modified the oscillation's period. These diferences produce amazing effects sometimes looking like a snake, a DNA molecule.
Nenhum comentário:
Postar um comentário