Potential Difference. Abbreviated P. D. Found on test curves. Synonymous with voltage.
Rate. Number of amperes for charge or discharge. Also used to express time for either.
Rectifier. Apparatus for converting alternating current into direct current.
Resistance. Material (usually lamps or wire) of low conductivity inserted in a circuit to retard the flow of current. By varying the resistance, the amount of current can be regulated. Also the property of an electrical circuit whereby the flow of current is impeded. Resistance is measured in ohms. Analogous to the impediment offered by wall of a pipe to flow of water therein.
Rheostat. An electrical appliance used to raise or lower the resistance of a circuit and correspondingly to decrease or increase the current flowing.
Rib. (See Bridge.)
Ribbed. (See Separator.)
Reversal. Reversal of polarity of cell or battery, due to excessive discharge, or charging in the wrong direction.
Rubber Sheets. Thin, perforated hard rubber sheets used in combination with the wood separators in some types of batteries. They are placed between the grooved side of the wood separators and the positive plate.
Sealing. Making tight joints between jar and cover; usually with a black, thick, acid-proof compound.