Replacement Pith Balls for Electroscope, 10-Pack Subcategory_Pressure and Gas Laws and a 1-degree protractor

and a 1-degree protractor

Plastic-bodied wave apparatus with eccentric discs that drive metal rods up and down as the handle turns

angular momentum

delivering wheel-driven power to a lamp or a Newton color disc

and 4-pole armature configurations on the same motor frame by swapping interchangeable enameled-copper armatures past a permanent bar magnet on a disc commutator

Replacement Pith Balls for Electroscope, 10-Pack Subcategory_Pressure and Gas Laws and a 1-degree protractorSpare pack of ten low mass pith balls sized for the standard pith ball electroscope, supplying replacements when the originals lose loft or split during repeated charging cycles.