Double Concave Glass Lens, 50mm Diameter, 250mm Focal Length, 3mm Thick Racks & Stands_Flask Stands 5A standard rheostat with oxidized

5A standard rheostat with oxidized constantan winding on a vitreous-enameled steel tube

Color-coded life-size brain model distinguishes cortical lobes

230mm disc graduated 0-360 degrees in 1-degree steps locks in any position alongside a rotatable lamp house and six magnetic acrylic elements for full ray-tracing studies of reflection and refraction

Compares radiant-heat absorption through paired surfaces and a white screen

Used to measure induced EMF as a magnet falls through a 100-turn coil on a 15mm acrylic tube

Double Concave Glass Lens, 50mm Diameter, 250mm Focal Length, 3mm Thick Racks & Stands_Flask Stands 5A standard rheostat with oxidizedSlim 3mm thick double concave glass lens at 50mm diameter and 250mm focal length, the diverging curvature paired with low mass for ray box mounts and lightweight optics setups.