# Léon Foucault

### By: Miranda Blankenship

• He was a french physicist
• He was born in Paris on September 18th, 1819
• He died in Paris on February 11th, 1868
• He was approximately 48 when he died
• He died of multiple sclerosis
• He would be 194 years old today
• Physicist~ An expert or a student in the study of physics

## Léon's Studies

• He studied Medicine
• He was scared of blood so later on he had to give it up
• After trying medicine he went to work on as a physicist
• He assisted to people by the names of Hippolyte Fizeau and Alfred Donne
Interesting Facts:
• An experiment was named after him when he had proved that light travels faster in air than in water
• This experiment was known as the "Foucault–Fizeau experiment"

## Foucault Pendulum

• A pendulum is something hanged from a fixed point and moved by inertia
• A pendulum helps us show how the earth spins and keep an ACCURATE time
• Léon performed precisely three demonstrations and the third got through
• The Foucault Pendulum is a pendulum that has a long wire that can swing in any direction and when it does it shows how the Earth rotates
• To understand the pendulum you must first know that the floor beneath it moves and makes it seem as if the pendulum was changing its on path
• Step 1: The pendulum has inertia acting on it as well as gravity to bring it back
• Step 2: The air resistance makes it swing only in straight arcs
• Step 3: Sometimes air currents throw it off by an inch or two
• Step 4: The pendulum is attached to the building and will travel laterally with the building but will not twist around the building even if the building were to twist around
• Thus where the floor moving comes in at, we notice that there is noting that can make the pendulum rotate but the floor rotates and the floor just so happens to be attached to the earth and thus we realize that the Earth rotates

## Importance

• His work was important to the field of science
• If it wasn't for Foucault we may have not known how the earth rotates for another 100 years or later