1. Hans Geiger 1882-1945 Information presented by Kemone Moodley and Sam Orchison

2. Personal Story Johannes Wilhelm Geiger was born on September 30 1882 Neustadt-an-der- Haardt, Germany. He was the son of Wilhelm Ludwig Geiger, a philosophy professor at the university of Erlangen and the eldest child of five children.  He studied at both the university of Munich and the university of Erlangen, majoring in in physics.  1906-1912, worked with Rutherford, helped Rutherford  1911, made the first version of the Geiger counter  1914, left England to go back to Germany, served as a military officer in World War 1  After World War 1 he went back to researching radioactivity from 1919-1945.  1920 married Elisabeth Heffter whom he later had three kids with  1928, while working in the University of Kiel, Geiger worked alongside physicist Walther Muller to improve Geiger counter.  I936, he along with 75 German physicists presented a paper to Hitler’s Education Ministry in protest of government interfering with science departments.  Continued to work at Technische Hochschule. Forced to flee his city in 1945 during World War 2.  Died on September 24, 1945.

3. Atom Idea  Through his experiments he assisted Rutherford in developing the theory that proposed that the nucleus of an atom occupies a very small volume.

4. Experiments  This study of atom scattering was fundamental in inspiring Rutherford’s nuclear theory of the atom, made in 1912, that in any atom, the nucleus occupies a very small volume at the centre.  Conducted experiments based on Rutherford’s detection of the release of alpha particles from radioactive substances.  He created the Geiger counter which detects radioactivity.  Through the Geiger counter, Hans Geiger was able to detect alpha particles in the nucleus of a helium atom.

5. Major Scientific Contribution  1911, in response to the experiments conducted on alpha particles, Geiger created an early version of the Geiger counter, a device that could count released alpha particles.  1925, alongside physicist Walther Muller, improved on the Geiger counter. This perfected version of the Geiger counter could locate a speeding alpha particle within about 1 cm in space and to within a hundred- millionth second.  Counter was used to confirm existence of light quantum.

6. Bibliography Websites: 1.http://www.notablebiographies.com/Fi-Gi/Geiger-Hans.htmlhttp://www.notablebiographies.com/Fi-Gi/Geiger-Hans.html 2.http://web.mit.edu/invent/iow/geiger.htmlhttp://web.mit.edu/invent/iow/geiger.html Books: 1. BcScience Chemistry 11