Zee Media Bureau/Philaso Kaping
New Delhi: French physicist Léon Foucault’s 194th birth anniversary is being celebrated with an interactive doodle of his most famous invention, the Foucault pendulum.
Born in 1819 to a Parisian publisher, Foucault pursued medicine which he later abandoned due to fear of blood. He went on to study physics and in time assisted and collaborated with Alfred Donne and Hippolyte Fizeau.
He conducted an experiment in 1850 known as the Foucault–Fizeau experiment to measure the speed of light. This experiment demonstrated that light travels more slowly through water than through air, thus driving the final nail in the coffin of Newton’s corpuscle theory of light.
His most famous work was the Foucault pendulum with which he demonstrated the rotation of the Earth on its axis. In 1851, Foucault suspended a pendulum from the dome of the Pantheon in Paris consisting of a 28kg brass-coated lead bob with a 67-metre long wire. The pendulum’s swing rotated clockwise 11° per hour, making a full circle once every 32.7 hours.
He also made a discovery which showed that the force required for the rotation of a copper disc becomes greater when it is made to rotate with its rim between the poles of a magnet, the disc at the same time becoming heated by the eddy current induced in the metal.
In 1857, he invented the Foucault polarizer and in the following year devised the Foucault knife-edge test to determine the shape of a reflecting telescope’s mirror.
Foucault passed away on February 11, 1868 possibly due to a rapidly developing case of multiple sclerosis.
His name is among those seventy-two of French scientists, engineers, and mathematicians which are engraved on the Eiffel Tower in recognition of their contributions.