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Name: Sarah W.
Status: educator
Age: 40s
Location: N/A
Country: N/A
Date: Thursday, April 25, 2002

How would one devise an experiment to find the charge of a proton?


Finding a charge on a proton directly would be difficult, for two reasons. First, producing free protons to work with is not easy. Protons tend to stick to their nuclei. Ionizing hydrogen might do the trick. Second, protons are too massive. A great deal of force (on the particle scale) is needed to make a proton do anything significant.

One way to deal with this is to find the charge of an electron. The charge of the proton and electron have charges of the same magnitude, but opposite sign. If this were not the case, most atoms would have a net charge. The most popular experiment I know of for this is the Millikan Oil Drop Experiment. It is not easy, but equipment for the experiment can be obtained. I know PASCO offers such a device, but I have never used it. I do not know whether it works well.

Dr. Ken Mellendorf
Physics Instructor
Illinois Central College

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