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Written by Nick Padula
Written by Vanshika Balayan


Living from June 13th, 1831 to November 5th, 1879, James Clerk Maxwell was a Scottish scientist who studied mathematical physics. Maxwell is widely acclaimed as "the father of modern physics"[http://www.clerkmaxwellfoundation.org/html/who_was_maxwell-.html]
Living from June 7th, 1862 to May 20th, 1879, Philipp Eduard Anton von Lenard was a German scientist who studied the physics behind cathode rays.[http://www.nobelprize.org/nobel_prizes/physics/laureates/1905/lenard-bio.html]


[[File:James_Clerk_Maxwell.png|thumb|James Clerk Maxwell.]]
[[File:lenard.jpg|thumb|Philipp Eduard Anton von Lenardl.]]


==Personal Life==
==Personal Life==


 
Lenard was a nationalist and a known ant-Semite. He was an active proponent of Nazi ideology and was an important role model for the "Deutsche Physik" movement


===Life and Education===
===Life and Education===


Maxwell was born in Edinburgh to an affluent family. He was described by his mother as a curious kid, even from the tender age of three. Maxwell attended The Edinburgh Academy. For his tertiary education, Maxwell studied at the University of Edinburgh and the University of Cambridge. At age 25, he became Professor of Physics at Marischal College in Aberdeen. He then moved to King's College in London and subsequently to Cambridge to be the Professor of Experimental Physics in 1871. He was married to Mary Dewar in 1858 [http://www.biography.com/people/james-c-maxwell-9403463#academic-background]
Philip was born in Bratislava (Hungary), on 7 June, 1862. His family originated from Tyrol and were German speakers. Philipp von Lenardis, his farther, was a wine merchant in Pressburg and his mother's name was Antonie Baumann.  Philipp attended the 'A Pozsonyi királyi katholikus fögymnasium´, which really had a big effect on him and made him want to pursue the sciences during his tertiary education. He then studied physics and chemistry in Vienna and Budapest in 1880. After receiving his doctorate and working under different scientists for a good bit of time, he moved to the University of Heidelberg in 1907 as the head of the Philipp Lenard Institute. The year 1905 brought him membership to the Royal Swedish Academy of Sciences and 1907 brought him membership at the Hungarian Academy of Sciences. [http://theconversation.com/when-science-gets-ugly-the-story-of-philipp-lenard-and-albert-einstein-43165]


==Work==
==Work==


===Saturn's Ring===
===Photoelectric Findings===
 
While working at Marischal College, Maxwell studied the rings of Saturn closely. He came to the conclusion that the planet's rings were comprised of small particles orbiting Saturn, as a solid ring would be unstable and break up [http://rsta.royalsocietypublishing.org/content/366/1871/1717]. This contradicted the accepted idea proposed by Christian Huygens in 1655 (but it did validate the claim in 1660 by poet and friend of Huygens, Jean Chapelain, that Saturn's rings are made of small satellites, a widely denounced claim). A gap in the outer part of Saturn's C ring is named after Maxwell.
 
[[File:PIA06540_Outer_C_Ring.jpg|thumb|View of the outer C Ring; the Maxwell Gap with the Maxwell Ringlet on its right side are above and right of center [https://en.wikipedia.org/wiki/Rings_of_Saturn#Maxwell_Gap_and_Ringlet].]]
 
===ElectroMagnetism===
 
In the 19th century, the connection between electricity and magnets was studied fervently by European scientists after the work of Hans Christian Oersted, Jean-Baptiste Biot and Félix Savart highlighted this connection. All of these scientists provided support for Maxwell's work, but [[Michael Faraday]] provided the most inspiration for Maxwell in his studies. However, Maxwell differed from Faraday in that he looked at the mathematical aspect of his research in addition to the physical aspects.
 
Maxwell's first step towards his electromagnetic theory was in his paper ''On Faraday's lines of force'' (1864), in which he proposed the idea of an incompressible fluid, the flow lines of which could represent the electric or magnetic field or current flow [http://rsta.royalsocietypublishing.org/content/366/1871/1849]. Here he explained that, in the case of electric fields, sources of the flow lines were positive charges and sinks were negative charges. In his subsequent paper, Maxwell introduced the idea of vortices, small, elastic objects that occupy space and have a small mass. Using this idea, he was able to derive Ampère's circuital law and to provide an explanation of Faraday's law of induction. In his model, these vortices were able to move in a conductor, but not in a dielectric (insulator). However, in a dielectric, the vortices can shift slightly due to an electric field.
 
===Equations===
 
In a paper titled ''A dynamical theory of the electromagnetic field'', Maxwell strove to make his theories more mathematical and less analogical. His four equations that resulted from this are as follows.
 
1.  Gauss' law for electricity:  <math> \oint \overrightarrow{E}  \bullet d  \overrightarrow{A}  = \frac{q} {\epsilon_0}</math>   


2. Gauss' law for magnetism:  <math> \oint \overrightarrow{B}  \bullet d  \overrightarrow{A}  = 0</math>
In 1888, Lenard began his study of cathode rays, which is where he made his biggest contributions. Lenard devised a method that made small metallic windows in the glass tubes that had allowed him to pass the rays emitted from the cathode into the laboratory or into an evacuated chamber. These windows were named "Lenard windows".
The creation of these windows then helped him observe the absorption of the rays. He saw that the absorption of the rays was proportional to the density of the material they were made to pass through. This contradicted the previous notional that cathode rays were some type of electromagnetic radiation. Additionally, Lenard saw that the rays appeared to be scattered by air after a short period of time, thus implying that cathode rays were negatively charged energetic particles. He called these quanta. This helped all physicists realize that electrons are constituent parts of an atom and that atoms mostly consist of empty space.


3.  Faraday's law of induction:  <math> \oint \overrightarrow{E} \bullet \overrightarrow{d s} = -\frac{d \Phi} {dt} </math> 
Lenard's most important observation was that the energy of a cathode ray is independent of the light intensity, but was greater for shorter wavelengths of light. These observations were then further explained by Albert Einstein in what he called the quantum effect. This theory showed that the energy of a cathode ray should be directly proportional to frequency by a factor of Planck's constant, h.


4. Ampere's law: <math> \oint \overrightarrow{B} \bullet \overrightarrow{d s} = \mu_0i + \frac{1} {c^2} \frac{\partial} {\partial t}  \int \overrightarrow{E}  \bullet d  \overrightarrow{A}</math>
Lenard actually ended up being a skeptic of Einstein's theories. However, he never went against Einstein's explanation of the photoelectric effect.
[[File:cathode.jpg|thumb|A Crooke's tube. The cathode rays travel in straight lines from the cathode (shown on the left) and strike the wall of the tube (shown on the right), which then makes it glow by fluorescence.]]


==Use by Other Scientists==
===Meteorological Findings===


Albert Einstein once said "The special theory of relativity owes its origins to Maxwell's equations of the electromagnetic field."[http://www.clerkmaxwellfoundation.org/html/who_was_maxwell-.html] Einstein was said to have a picture of Maxwell on his wall in his study. [http://inthemindseyedyslexicrenaissance.blogspot.com/2009/08/thinking-in-pictures-einstein-and.html]
Lenard was the first person to study the separation of electric charges that accompanies the aerodynamic break up of droplets of water. This is known as "spray electrification", "the waterfall effect", or the "Lenard effect". Lenard conducted studies that explored the size and shape distributions of raindrops. To do this, he constructed a wind tunnel in which water droplets of different sizes cold be held stationary for a short period of time. This helped him recognize that large raindrops are not tear-drop shaped, but are shaped more like a burger bun.


== See also ==
[[File:Lenard-e.gi.jpg|thumb| A water droplet forms an electric double layer. ]]


Other famous scientists relating to Maxwell include:
===Awards===


[[Michael Faraday]]
Royal Society Rumford Medal- 1896
Italian Society of Sciences Matteucci Medal- 1896
French Academy of Sciences Prix La Caze- 1897
Franklin Institute Franklin Medal- 1932
Nobel Prize for Physics- 1905


[[Andre Marie Ampere]]
=="Deutsche Physik"==


[[Albert Einstein]]
Lenard was known as a strong German nationalist. He had a strong distaste for "English Physics" because he believed that it stole its ideas from Germany. He was a strong proponent and a member of the National Social Party. Lenard served as the Chief of Aryan physics under Adolf Hilter.
Lenard's strong belief and proposition for German physics led him to looking at all other physicists and their theories with great skepticism, especially Albert Einstein. His book, ''Great Men in Science, a History of scientific progress'' clearly showed his dislike for certain scientists. He even used to refer to Einstein as the "Jewish fraud" of relativity.


[[Edwin Hall]]
[[File:Swastika4.jpg]]


==References==
==References==


1. https://en.wikipedia.org/wiki/Rings_of_Saturn#Maxwell_Gap_and_Ringlet
1. http://www.nobelprize.org/nobel_prizes/physics/laureates/1905/lenard-bio.html


2. http://www.clerkmaxwellfoundation.org/html/who_was_maxwell-.html
2. http://theconversation.com/when-science-gets-ugly-the-story-of-philipp-lenard-and-albert-einstein-43165


3. http://www.biography.com/people/james-c-maxwell-9403463#saturns-rings
3. http://www.rawstory.com/2015/06/when-science-gets-ugly-the-story-of-philipp-lenard-and-albert-einstein/


4. http://rsta.royalsocietypublishing.org/content/366/1871/1717
4. hhttp://www.britannica.com/biography/Philipp-Lenard


5. http://rsta.royalsocietypublishing.org/content/366/1871/1849
5. http://www.nndb.com/people/441/000099144/


7. http://inthemindseyedyslexicrenaissance.blogspot.com/2009/08/thinking-in-pictures-einstein-and.html
7. http://www.einstein-website.de/biographies/lenard_content.html


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

Latest revision as of 15:19, 4 December 2015

Written by Vanshika Balayan

Living from June 7th, 1862 to May 20th, 1879, Philipp Eduard Anton von Lenard was a German scientist who studied the physics behind cathode rays.[1]

Philipp Eduard Anton von Lenardl.

Personal Life

Lenard was a nationalist and a known ant-Semite. He was an active proponent of Nazi ideology and was an important role model for the "Deutsche Physik" movement

Life and Education

Philip was born in Bratislava (Hungary), on 7 June, 1862. His family originated from Tyrol and were German speakers. Philipp von Lenardis, his farther, was a wine merchant in Pressburg and his mother's name was Antonie Baumann. Philipp attended the 'A Pozsonyi királyi katholikus fögymnasium´, which really had a big effect on him and made him want to pursue the sciences during his tertiary education. He then studied physics and chemistry in Vienna and Budapest in 1880. After receiving his doctorate and working under different scientists for a good bit of time, he moved to the University of Heidelberg in 1907 as the head of the Philipp Lenard Institute. The year 1905 brought him membership to the Royal Swedish Academy of Sciences and 1907 brought him membership at the Hungarian Academy of Sciences. [2]

Work

Photoelectric Findings

In 1888, Lenard began his study of cathode rays, which is where he made his biggest contributions. Lenard devised a method that made small metallic windows in the glass tubes that had allowed him to pass the rays emitted from the cathode into the laboratory or into an evacuated chamber. These windows were named "Lenard windows". The creation of these windows then helped him observe the absorption of the rays. He saw that the absorption of the rays was proportional to the density of the material they were made to pass through. This contradicted the previous notional that cathode rays were some type of electromagnetic radiation. Additionally, Lenard saw that the rays appeared to be scattered by air after a short period of time, thus implying that cathode rays were negatively charged energetic particles. He called these quanta. This helped all physicists realize that electrons are constituent parts of an atom and that atoms mostly consist of empty space.

Lenard's most important observation was that the energy of a cathode ray is independent of the light intensity, but was greater for shorter wavelengths of light. These observations were then further explained by Albert Einstein in what he called the quantum effect. This theory showed that the energy of a cathode ray should be directly proportional to frequency by a factor of Planck's constant, h.

Lenard actually ended up being a skeptic of Einstein's theories. However, he never went against Einstein's explanation of the photoelectric effect.

Error creating thumbnail: sh: /usr/bin/convert: No such file or directory Error code: 127
A Crooke's tube. The cathode rays travel in straight lines from the cathode (shown on the left) and strike the wall of the tube (shown on the right), which then makes it glow by fluorescence.

Meteorological Findings

Lenard was the first person to study the separation of electric charges that accompanies the aerodynamic break up of droplets of water. This is known as "spray electrification", "the waterfall effect", or the "Lenard effect". Lenard conducted studies that explored the size and shape distributions of raindrops. To do this, he constructed a wind tunnel in which water droplets of different sizes cold be held stationary for a short period of time. This helped him recognize that large raindrops are not tear-drop shaped, but are shaped more like a burger bun.

A water droplet forms an electric double layer.

Awards

Royal Society Rumford Medal- 1896 Italian Society of Sciences Matteucci Medal- 1896 French Academy of Sciences Prix La Caze- 1897 Franklin Institute Franklin Medal- 1932 Nobel Prize for Physics- 1905

"Deutsche Physik"

Lenard was known as a strong German nationalist. He had a strong distaste for "English Physics" because he believed that it stole its ideas from Germany. He was a strong proponent and a member of the National Social Party. Lenard served as the Chief of Aryan physics under Adolf Hilter. Lenard's strong belief and proposition for German physics led him to looking at all other physicists and their theories with great skepticism, especially Albert Einstein. His book, Great Men in Science, a History of scientific progress clearly showed his dislike for certain scientists. He even used to refer to Einstein as the "Jewish fraud" of relativity.

References

1. http://www.nobelprize.org/nobel_prizes/physics/laureates/1905/lenard-bio.html

2. http://theconversation.com/when-science-gets-ugly-the-story-of-philipp-lenard-and-albert-einstein-43165

3. http://www.rawstory.com/2015/06/when-science-gets-ugly-the-story-of-philipp-lenard-and-albert-einstein/

4. hhttp://www.britannica.com/biography/Philipp-Lenard

5. http://www.nndb.com/people/441/000099144/

7. http://www.einstein-website.de/biographies/lenard_content.html

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