In the Milikian oil drop experiment, an atomizer (a sprayer with a fine nozzle) is used to introduce tiny oil droplets between two oppositely charged parallel plates held in a vacuum chamber. Some of the droplets pick up excess electrons. The charge on the plate is adjusted so that the electric force on the excess electrons exactly balances the weight of the droplet, leaving the droplets levitating. The resulting equilibrium allows one to measure the electric charge of a droplet. If the droplets have a diameter of about 0.2mm, and the E-field between the plates is moderately strong 30,000 N/C, estimate how many excess electrons would be needed on the drop so that the electric force could hold the weight of the drop. Given: e = 1.6 x 10-19 C ; Fnet = ma ; F = qE ; Poil ͌800kg/m3

In the Milikian oil drop experiment, an atomizer (a sprayer with a fine nozzle) is used to introduce tiny oil droplets between two oppositely charged parallel plates held in a vacuum chamber. Some of the droplets pick up excess electrons. The charge on the plate is adjusted so that the electric force on the excess electrons exactly balances the weight of the droplet, leaving the droplets levitating. The resulting equilibrium allows one to measure the electric charge of a droplet. If the droplets have a diameter of about 0.2mm, and the E-field between the plates is moderately strong 30,000 N/C, estimate how many excess electrons would be needed on the drop so that the electric force could hold the weight of the drop. Given: e = 1.6 x 10-19 C ; Fnet = ma ; F = qE ; Poil ͌800kg/m3

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter20: Electric Potential And Capacitance

Section: Chapter Questions

Problem 69P

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