Léon Foucault: Difference between revisions

From Physics Book
Jump to navigation Jump to search
No edit summary
No edit summary
 
(10 intermediate revisions by the same user not shown)
Line 7: Line 7:
Born Jean Bernard Léon Foucault, Foucault was born on September 18, 1819 to a Parisian publisher. Due to his family's education and access to resources, Foucault was home schooled for the majority of his childhood, before leaving home to study medicine. He quickly discovered that due to his blood phobia, medicine was not the field for him. In order to continue academic pursuits Léon began studies in physics. Initially focusing on optics, Foucault worked on photographic processes, before becoming an assistant to [[Alfred Donné]], working with microscopic observation.
Born Jean Bernard Léon Foucault, Foucault was born on September 18, 1819 to a Parisian publisher. Due to his family's education and access to resources, Foucault was home schooled for the majority of his childhood, before leaving home to study medicine. He quickly discovered that due to his blood phobia, medicine was not the field for him. In order to continue academic pursuits Léon began studies in physics. Initially focusing on optics, Foucault worked on photographic processes, before becoming an assistant to [[Alfred Donné]], working with microscopic observation.


After finishing his term with  Alfred Donné, Léon partnered with [[Hippolyte Fizeau]] in order to study properties of visible light generated by the sun. In 1850 the two would conduct experiments detecting the speed of light through different mediums, effectively disproving Newton's theory of light.
After finishing his term with  Alfred Donné, Léon partnered with [[Hippolyte Fizeau]] in order to study properties of visible light generated by the sun. In 1850 the two would conduct experiments detecting the speed of light through different mediums, effectively disproving Newton's theory of light, as well as determining the speed of light within 1% of the modern accepted value. His work with Pendulums would earn him further renown when, in 1851, he presented the Foucault pendulum, a simple experiment proving the rotation of the earth. The experiment' success and public appeal led Foucault to design a similar experiment with a device he would name the [[gyroscope]]. His work publicizing science, coupled with his work on light and optics would earn Foucault both the [[Royal Society]]'s Copley award and a position at the Parisian Imperial Observatory in 1855.
 
At the Imperial Observatory Foucault would begin work studying magnets, eventually studying eddy currents, before returning to the field of optics. After designing a device to safely view the sun through a telescope, Foucault designed a method of testing the shape of mirrors in telescopes. IN his final years, Foucault returned to the Roman Catholic church, and later passed away due to multiple sclerosis on February 11, 1868.  
==Notable works==
==Notable works==


=== Foucault's Pendulum ===
=== Foucault's Pendulum ===
[[File:pendulumfree.gif|thumb|300px|Foucault's Pendulum in action]]
Foucault's Pendulum is based on the premise that a free floating pendulum set in motion will maintain it's path in space with respect to the axis it rotates about. The design consists of a long pendulum fixed only in the z direction at the pivot, with  large weight at the bottom. Once set in motion the pendulum would maintain it's plane of motion with respect to the top and bottom of the z-axis, the pivot and core of earth respectively. Tracing the path of the pendulum along the ground below it, however, will show, every except at the equator, a non linear path, indicating that the surface was rotating with respect to the plane of action of the pendulum.


=== Measurement of the speed of light ===
=== Measurement of the speed of light ===
[[File:solfoucault.jpg|thumb|300px|The Fouault-Fizeau Experiment]]
Working with Fizeau, Foucault designed a system to accurately measure the speed of light. Using a laser as a light source, beam was fired at a continuously rotating mirror, deflected to a second stationary mirror, back to the rotating mirror, and to the location of the laser. By measuring the distance from the projected beam from the source, and taking into account the distances involved along with the rate of rotation of the mirror, Foucault was able to predict the speed of light to be 298000 km/s, only 0.6% off from the modern accepted value for the speed of light.


*The Index of Refraction: the ratio of the speed of light through a vacuum to the speed of light in the medium. Written as: <math>n=\frac{c}{v}</math>, where
==Awards and Recognitions==
**c=speed of light in a vacuum
*Copley Medal
**v=speed of light in medium
*Member of the Royal Society
Note that the index of refraction can never be less than one, since <math>\frac{c}{c}=1</math>.
*Member of the [[Bureau des Longitudes]]
*Snell's Law: size of the angle of refraction, or how much the light bends. Written as:<math>n_1\sin\theta_1=n_2\sin\theta_2</math>, where
*Name Inscribed in the Eiffel Tower
**<math>n_1</math>=index of refraction of medium 1
*Officer in the [[Legion of Honour]]
**<math>n_2</math>=index of refraction of medium 2
*Asteroid [[5668 Foucault]] named in his honor
**<math>\theta_1</math>=angle of incidence
**<math>\theta_2</math>=angle of refraction.
 


== See also ==
*Foucault's Pendulum
**http://www.animations.physics.unsw.edu.au/jw/foucault_pendulum.html
**http://www.geophysik.uni-muenchen.de/outreach/foucault-pendulum
*Foucault-Fizeau Apparatus
**http://www.speed-light.info/measurement.htm


== See also ==


*[[Color Light Wave]]
*[[Wave-Particle Duality]]


===External links===
==References==
http://www-rohan.sdsu.edu/~aty/explain/optics/refr.html
http://www-history.mcs.st-andrews.ac.uk/Biographies/Foucault.html


http://ocw.mit.edu/courses/mechanical-engineering/2-71-optics-spring-2009/video-lectures/lecture-2-reflection-and-refraction-prisms-waveguides-and-dispersion/MIT2_71S09_lec02.pdf
http://www.famousscientists.org/leon-foucault/


==References==
https://en.wikipedia.org/wiki/File:Foucault-rotz.gif
https://en.wikipedia.org/wiki/Refracting_telescope


http://www-rohan.sdsu.edu/~aty/explain/optics/refr.html
http://www.daviddarling.info/encyclopedia/S/speedlight.html


[[Category:Optics]]
[[Category:Notable Scientists]]

Latest revision as of 18:32, 5 December 2015

Claimed by PierreR


Biography

Foucault

Born Jean Bernard Léon Foucault, Foucault was born on September 18, 1819 to a Parisian publisher. Due to his family's education and access to resources, Foucault was home schooled for the majority of his childhood, before leaving home to study medicine. He quickly discovered that due to his blood phobia, medicine was not the field for him. In order to continue academic pursuits Léon began studies in physics. Initially focusing on optics, Foucault worked on photographic processes, before becoming an assistant to Alfred Donné, working with microscopic observation.

After finishing his term with Alfred Donné, Léon partnered with Hippolyte Fizeau in order to study properties of visible light generated by the sun. In 1850 the two would conduct experiments detecting the speed of light through different mediums, effectively disproving Newton's theory of light, as well as determining the speed of light within 1% of the modern accepted value. His work with Pendulums would earn him further renown when, in 1851, he presented the Foucault pendulum, a simple experiment proving the rotation of the earth. The experiment' success and public appeal led Foucault to design a similar experiment with a device he would name the gyroscope. His work publicizing science, coupled with his work on light and optics would earn Foucault both the Royal Society's Copley award and a position at the Parisian Imperial Observatory in 1855.

At the Imperial Observatory Foucault would begin work studying magnets, eventually studying eddy currents, before returning to the field of optics. After designing a device to safely view the sun through a telescope, Foucault designed a method of testing the shape of mirrors in telescopes. IN his final years, Foucault returned to the Roman Catholic church, and later passed away due to multiple sclerosis on February 11, 1868.

Notable works

Foucault's Pendulum

Foucault's Pendulum in action

Foucault's Pendulum is based on the premise that a free floating pendulum set in motion will maintain it's path in space with respect to the axis it rotates about. The design consists of a long pendulum fixed only in the z direction at the pivot, with large weight at the bottom. Once set in motion the pendulum would maintain it's plane of motion with respect to the top and bottom of the z-axis, the pivot and core of earth respectively. Tracing the path of the pendulum along the ground below it, however, will show, every except at the equator, a non linear path, indicating that the surface was rotating with respect to the plane of action of the pendulum.

Measurement of the speed of light

The Fouault-Fizeau Experiment

Working with Fizeau, Foucault designed a system to accurately measure the speed of light. Using a laser as a light source, beam was fired at a continuously rotating mirror, deflected to a second stationary mirror, back to the rotating mirror, and to the location of the laser. By measuring the distance from the projected beam from the source, and taking into account the distances involved along with the rate of rotation of the mirror, Foucault was able to predict the speed of light to be 298000 km/s, only 0.6% off from the modern accepted value for the speed of light.

Awards and Recognitions

See also


References

http://www-history.mcs.st-andrews.ac.uk/Biographies/Foucault.html

http://www.famousscientists.org/leon-foucault/

https://en.wikipedia.org/wiki/File:Foucault-rotz.gif

http://www.daviddarling.info/encyclopedia/S/speedlight.html