Robert+Millikan

__ Robert Millikan __ Robert A. Millikan was born on March 22, 1868 and died December 19, 1953. He received a Bachelor's degree in the classics from Oberlin College in 1891, and received his doctorate in physics from Columbia University in 1895. Millikan was the first person to earn a Ph.D. from that department. Robert Millikan was an American experimental physicist honored with the Nobel Prize for Physics in 1923 for his measurement of the elementary electronic charge and for his work on the photoelectric effect.

The elementary electronic charge is the electric charge carried by a single proton, or equivalently, the opposite of the electric charge carried by a single electron.

HOW DID HE MEASURE THE ELEMENTARY ELECTRONIC CHARGE? Millikan used the oil drop experiment to determine the charge of the electron in 1909. The Millikan oil-drop experiment was far superior to previous determinations of the charge of an electron. Where other workers had attempted to measure the quantity by observing the effect of an electric field on a cloud of water droplets, Millikan used single drops, first of water and then, when he found these evaporating, of oil.



__OIL DROP EXPERIMENT __ Millikan sprayed tiny oil droplets and had them fall through a small charged hole into a closed area where the oil droplets had charged. Then he would "introduce" this to an electric field, in which the charged oil particles would move up and down. By observing the speed of the particles, he determined the charge on electrons.

media type="youtube" key="XMfYHag7Liw" width="560" height="315" In the photoelectric effect, electrons are emitted from solids, liquids, or gases when they absorb energy from light. When Einstein published his paper on the particle theory of light, Millikan was convinced that it had to be wrong, because of the vast body of evidence that had already shown that light was a wave. By 1910, he had proved that Einstein's formula for this effect was correct, which was against his own expectations. Distraction pages: Oil drop experiment that is not in english... http://www.youtube.com/watch?v=kUbsUGjRlTk Robert Millikan rap http://www.youtube.com/watch?v=NIo1t8GBRl8 www.twitter.com and Instagram Random pictures on google images Cited Pages: http://en.wikipedia.org/wiki/Robert_Andrews_Millikan http://en.wikipedia.org/wiki/Elementary_charge http://en.wikipedia.org/wiki/Photoelectric_effect [] [] []