How Does Foucault’s Pendulum Prove the Earth Rotates?
This elegant scientific demonstration has been delighting everyday people for nearly 200 years
By Alicia Ault
February 2, 2018
On February 3, 1851, a 32-year-old Frenchman—who’d dropped out of medical school and dabbled in photography—definitively demonstrated that the Earth indeed rotated, surprising the Parisian scientific establishment.
Acting on a hunch, Léon Foucault had determined that he could use a pendulum to illustrate the effect of the Earth’s movement. He called together a group of scientists, enticing them with a note declaring, “You are invited to see the Earth turn.†Foucault hung a pendulum from the ceiling of the Meridian Room of the Paris Observatory. As it swept through the air, it traced a pattern that effectively proved the world was spinning about an axis.
Read more:
https://www.smithsonianmag.com/smithsonian-institution/how-does-foucaults-pendulum-prove-earth-rotates-180968024/#8QfqWCupsx8KXh97.99