CHAPTER 17
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SMALL CURRENT TECHNIQUE
17—1.
Introduction.—Special instruments are used to measure
electrical currents which are too small to be detected With galvanometers. These currents, Which are of the order of magnitüde of
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10—8_ to 10—17 ampere, are
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often encountered inWork
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With radio-active
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etc., and
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consist of streams of
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paratively large humbers of
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charged particles.
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measurement Will be
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cases where there are
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so few moving Charges that
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