Double Concave Glass Lens, 50mm Diameter, 100mm Focal Length, 16.5mm Thick Subcategory_Alternative Energy this wooden block-and-tackle apparatus lets

this wooden block-and-tackle apparatus lets students count supporting strands and measure how each added pulley reduces effort

LED circuits

Hand-painted animal cell model reveals organelle structures

expanding and closing to suit different optical-component sizes on a single bench-mounted holder

this single-phase rheostat carries oxidized constantan winding with 4mm safety socket terminals

Double Concave Glass Lens, 50mm Diameter, 100mm Focal Length, 16.5mm Thick Subcategory_Alternative Energy this wooden block-and-tackle apparatus letsDouble concave glass lens at 50mm diameter and 100mm focal length, a thick 16. 5mm blank with optically true surfaces, the diverging curvature producing virtual upright images for refraction work.