The ring has three holes for illumination and one for viewing through a microscope. A uniform electric field is created between them. Simplified scheme of MillikanвЂ™s oil-drop experimentThis apparatus has a parallel pair of horizontal metal plates. Alternatively, charge could be induced by including an ionizing radiation source (such as an X-ray tube). The oil drops became electrically charged through friction with the nozzle as they were sprayed. A fine mist of oil droplets was sprayed into a chamber above the plates. Four holes were cut into the ring-three for illumination by a bright light and another to allow viewing through a microscope. A ring of insulating material was used to hold the plates apart. Ordinary oil would evaporate under the heat of the light source, causing the mass of the oil drop to change over the course of the experiment.Д«y applying a potential difference across a parallel pair of horizontal metal plates, a uniform electric field was created in the space between them.

Millikan and Fletcher discovered it was best to use an oil with an extremely low vapor pressure, such as one designed for use in a vacuum apparatus. The apparatus incorporated a pair of metal plates and a specific type of oil. The figure below shows a simplified scheme of MillikanвЂ™s oil drop experiment. Charge of an Electron: MillikanHow did scientists discover how much negative charge an electron had? Robert Millikan and Harvey Fletcher used the oil drop experiment. They proposed that this was the charge of a single electron. They calculated this value to be 1.5924 Г— 10 в€’19Coulombs (C), which is within 1% of the currently accepted value of 1.602176487 Г— 10 в€’19 C. By repeating the experiment, they confirmed that the charges were all multiples of some fundamental value. Using the known electric field and the values of gravity and mass, Millikan and Fletcher determined the charge on oil droplets in mechanical equilibrium. The density of the oil was known, so Millikan and Fletcher could determine the dropletsвЂ™ masses from their observed radii (since from the radii they could calculate the volume and thus, the mass). They suspended tiny charged droplets of oil between two metal electrodes by balancing downward gravitational force with upward drag and electric forces. In 1909, Robert Millikan and Harvey Fletcher conducted the oil drop experiment to determine the charge of an electron. electronThe subatomic particle having a negative charge and orbiting the nucleus the flow of electrons in a conductor constitutes electricity.oil drop experimentExperiment performed by Robert Millikan and Harvey Fletcher in 1909 to measure the charge of the electron.Therefore, the charge on the oil drop was calculated using formula Q = rac Millikan found that the charge of a single electron was 1.6 x 10 -19 C. When the charged drops fell at a constant rate, the gravitational and electric forces on it were equal.

Electrically charged oil droplets entered the electric field and were balanced between two plates by altering the field.

MillikanвЂ™s apparatus contained an electric field created between a parallel pair of metal plates, which were held apart by insulating material.

Before this experiment, existence of subatomic particles was not universally accepted.

MillikanвЂ™s oil drop experiment measured the charge of an electron.

Oil 7 days to die