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Summary
DescriptionWalter Kaufmann measurement of electron charge to mass ratio.svg
English: Walter Kaufmann's experimental measurement of electron charge to mass ratio (1901 - 1905). (a) Front view shows uniformly accelerated motion produced by the E field between the charged condenser plates. (b) Side view shows circular motion produced by the B field. (c) The photographic plate records a curved line whose measurements allow computation of e/m for different values of v.
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