This applet models the 1909 Millikan experiment. Droplets of oil are fed into the apparatus by a nebulizer, and then bombarded by X-rays to ionize the droplets. In the absence of an electric field, the droplets fall under only the force of gravity. They quickly stabilize their velocity due to the resistance of the viscosity of air.
When the electric field is turned on and adjusted, the particles move based on their mass and effective charge. The spectacular result of the experiment was to show that electric charge is quantized (i.e., it comes in fixed amounts). This applet will be used to recreate the experiment, and attempt to determine the magnitude of the charge on the electron.
The density of the droplets in this applet, ρ, is 1.00 g cm -3. The viscosity of air, η, is 1.81 × 10 -5 N s m -2. The distance d between the red lines is 10 -4 m.
.See here for a complete description of how to perform the experiment, and how to process your data.
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