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460 BCE
Democritus
Democritus was born in Abduera( Greece) -
Period: 455 BCE to 425 BCE
Democritus Life
(The dates aren't too clear but it was during his life time)
He was born into a wealth family and was and entertainer for the army of Xerxes,(Persian ruler at the time) Because of this he was given the opportunity to learn astronomy and theology from these Magi. It is said that he traveled to Egypt, Ethiopia, Persia, and even India. Then at certain point he became a student of Leucippus which later he used some of Leuippus's atomic theory and expanded on it. -
400 BCE
Democritus Contribution
They have called him "The Laughing Philosopher" because they say that he was always very cheerful.His contribution towards the atomic theory basically said that the universe and all matter follow the same rules/principles. He also believed that matter were made up of really really small particles that they called "atomos/atoms".Also that atoms are indestructible, always in motion, different kinds of atoms which are all different. He did this over observation more than actual experiments. -
370 BCE
Democritus Dies
Democritus passes away in 370 -
John Dalton
He was born on September 6, 1766, in Eaglesfield, England. When he first started his career he figured out that he suffered red-green color blindness. As a child he wanted to get a good education, but his family was financially limited, so he knew he had to help with the families finances. -
John Dalton Early Life
He attended a Quaker school and started teaching in that school at age 12, then he went to work in as a farmhand at age 14 but a year later he returned to teaching. He became the principal of that school and stayed there until 1793, then he became a tutor of math and philosophy in the New College in Manchester. This lead to him join the Manchester Literary and Philosophical Society which gave him access to the laboratory.. -
Dalton's Contribuation
In his," A New System of Chemical Philosophy", he proposes that an element is composed of atoms, identical atoms of an element are identical, they can’t be created or destroyed, and that different elements combined to form a compound. His experiments led him to believe that atoms constantly combine in simple rations meaning the they are proportional. -
Dalton's Death
He died after having his second stroke. -
J.J Thomas
Joseph John Thomas was born on December 18, 1856 in a suburb of Manchester named Cheetham Hill -
Max Planck
Max Karl Ernst Ludwig Planck born on April 23, 1858, in Kiel Germany. His father was Professor of Constitutional Law in the University of Kiel -
Robert Andrews Millikan
Robert Andrew Millikan was born in Morris, Illinois and was the 2nd son of Reverend Silas. His early life was very known, but he did attend Maquoketa High school, then he worked as a court reporter, but he went to Oberlin College in 1886; as an undergraduate his favorite subjects were math and Greek(that's pretty cool). Then he taught in elementary physics in 1891. in 1893 he mastered physics and was appointed Fellow in Physics at Colombia University. Then 2 years later he received his Ph. D -
Period: to
J.J Thomas Career
Thomas started his schooling at the Owens College in Manchester, in 1870, but in 1876 he went to Trinity College in Cambridge, and became a member ever since. He became a Lecturer in 1883 and then became Master 1918. He was the Head of the department of experimental physics. He also traveled to America to give lectures on electricity and matter in Yale. And i think he might of like plum pudding -
Ernest Rutherford
Ernest Rutherford was born in Nelson, New Zealand on August 30, 1871. He had 7 siblings and both of his parents had migrated to New Zealand from different countries one being English and the other being Scottish. He started his early education in government(public) schools and entered the Nelson Collegiate School at age 16. -
Niels Bohr
Neils Henrik David Bohr was born on October 7 1885, in Copenhagen Denmark. He was born into a family that was known for their intelligence so it was easier for him to get involved and get a good education. He got the Nobel Prize award when he was studying in Copenhagen University. -
Period: to
Ernest Rutherford Career
He started off his career with a University scholarship which gave him the opportunity to go to the University of New Zealand, then he entered Canterbury College. He graduated with a M.A. in Physics Science and Mathematics in 1893. In 1894 he received an 1851 Exhibition Science Scholarship, this let him go study at Trinity College, Cambridge, as a research student under J.J. Thomas and got his B.A Research in 1987.Then he took J.J Thomas spot as the Head Director of Physics at Cambridge. -
James Chadwick
James was born on October 20, 1891 in Cheshire, England. He went to Manchester High school then entered Manchester University in 1908. -
J.J Thomas Contribution
Thomas used a cathode ray tube and figured out that there was negatively charged particles, he also studied positive charges in neon gas.He added to the atom by saying that there are both negative and positively charged particles in the atom. The example he used was plum pudding; the positively charged particles is the pudding, and the plums were the electrons. “Plum Pudding” model -
Period: to
Max Planck Career
He started off his studies at the University of Munich and Berlin, his teachers included Helmholtz and Kirchhoff. In 1879 he received his doctorate of philosophy at Munich. He was and associate Professor of Theoretical Physics at Kiel until 1889, and took Kirchhoff spot as Professor at Berlin University then retired in 1926. And be came president of the Society for the Promotion of Science until 1937 -
Period: to
James Chadwick Career
He went to Manchester University in 1908 and graduated from the Honours School of Physics in 1911 and spent time as a student of Rutherford in the Lab. at Manchester. He was awarded the 1851 Exhibition Scholarship and went to Berlin to work under Professor H. Geiger. Then he later returned to work under Rutherford again and studied the structure of the atomic nuclei. -
Ernest Rutherford Contribution
He did a set of experiment with some of his fellow colleagues now known as the Gold Foil Experiment. They used alpha particles, and they aimed them at the gold foil and recorded the how the beam traveled through the foil. They saw that most of the beam went though but small particles deflected off. So his conclusion was that the atom is small dense and positively charged nucleus with negative charges surrounding it. Summed up he figured out that there was a nucleus. -
Robert Millikan
The Oil Drop Experiment was used to try to determine the measurement of an electron charge, before this it wasn't accepted that subatomic particles existed yet since it hadn't be proven yet. That was his goal to show that electrons could be calculated. They did this by dropping oil between electrically charged plates and calculated the force of the droplets. The concluded that the charge of an electron is 1.5924(17) x 10^-19 C. Coulombs are the SI unit of electric charge -
Niels Bohr Career
He Entered the Copenhagen University and was taught by Professor C. Christiansen, this led him to take his Masters degree in 1909 and his doctor's degree in 1911. He worked under the guidance of J.J Thomas and Professor Rutherford while working under their command he was making his own theories. This cause him to try to introduce new concepts using information from all the others to formulate his own. -
Neils Bohr's Contribution
He basically figured out and developed a theory that we still used today. He used a little bit of quantum theory and the theory for the hydrogen atom and devised that they can only transfer in a certain way. Electrons move in a circular/orbital path around the nucleus and they can jump to an obit with a lower energy. -
Max Planck Contribution
He created the quantum theory that explains the nature and behavior of matter and the energy on the atomic and subatomic level. Meaning he was seeing the behavior of the atoms, light, and waves at the smallest points(subatomic Particles) These are later known as photons. He got the Nobel Prize for this in 1918 -
James Chadwick
He used the alpha particles to spray beryllium atoms. While doing this he noticed that a unknown radiation was being created. Chadwick used this information and concluded that particles had a neural charge and the approximate mass of a proton.( Found the neutron) -
Ernest Rutherford
He died from a strangulated hernia -
J.J Thomas
He passed away August 30, 1940 -
James Chadwick
He died in July 24, 1974 -
Max Planck
He died in Göttingen, Germany on October 4, 1947 -
Niels Bohr
He died in November 18, 1962 in Copenhagen Denmark.
