Atomizer Bright light Oil droplet Figure 30.9 The Millikan oil drop experiment produced the first accurate direct measurement of the charge on electrons, one of the most fundamental constants in nature. Fine drops of oil become charged when sprayed. Their movement is observed between metal plates with a potential applied to oppose the gravitational force. The balance of gravitational and electric forces allows the calculation of the charge on a drop. The charge is found to be quantized in units of –1.6 x 10-19 C, thus determining directly the charge of the excess and missing electrons on the oil drops.

Atomizer Bright light Oil droplet Figure 30.9 The Millikan oil drop experiment produced the first accurate direct measurement of the charge on electrons, one of the most fundamental constants in nature. Fine drops of oil become charged when sprayed. Their movement is observed between metal plates with a potential applied to oppose the gravitational force. The balance of gravitational and electric forces allows the calculation of the charge on a drop. The charge is found to be quantized in units of –1.6 x 10-19 C, thus determining directly the charge of the excess and missing electrons on the oil drops.

College Physics

1st Edition

ISBN:9781938168000

Author:Paul Peter Urone, Roger Hinrichs

Publisher:Paul Peter Urone, Roger Hinrichs

Chapter30: Atomic Physics

Section: Chapter Questions

Problem 56PE: Integrated Concepts In a Millikan oil-drop experiment using a setup like that in Figure 30.9, a...

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