One-Meter Single-Wire Potentiometer Item Type_Mug deflecting visibly in the presence

deflecting visibly in the presence of a charged object to reveal both charge presence and polarity

Standard rheostat with oxidized constantan winding on a vitreous-enameled steel tube and a heavy-duty sliding contact

Used to produce concentric Newton's rings under monochromatic light

Carbon anode-and-cathode pair pre-fitted in a rubber bung

Stable-resistance 22 SWG bare constantan wire on a 125g reel

One-Meter Single-Wire Potentiometer Item Type_Mug deflecting visibly in the presenceOne meter single wire potentiometer with 24 SWG constantan wire stretched along a millimeter scale, mounted on a polished hardwood base with heavy plated brass end plates and 4mm sockets.