Definition of ballistic galvanometer in English:
ballistic galvanometer
noun
A moving-coil galvanometer whose coil has a large moment of inertia and a slow swing, so that the instrument responds to the quantity of charge passed (rather than the size of the current) and is suitable for measuring very small currents.
Origin
Late 19th century; earliest use found in William Thomson (1819–1890), archbishop of York.
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