An electroscope indicates electrical charging through the motion of conducting leaves, fibers or another movable conductor. When charge is supplied to connected leaves, like-sign charge on them produces repulsion and visible separation.
A nearby charged object can also redistribute charge by electrostatic induction, producing a deflection without transferring net charge to the isolated instrument. Touching and withdrawing the object tests a different process from merely bringing it close. Deflection is not a universal direct readout of charge magnitude: geometry, leakage and any initial charge determine the response, and a charge-sign test needs a known reference.
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