Round Convex Glass Mirror, 75mm Diameter, 200mm Focal Length Material_Steel Wooden fulcrum-balance simple-machine model with

Wooden fulcrum-balance simple-machine model with a sliding pivot

Suspends a 20mm solid brass cube from spring scales for Archimedes'-principle and buoyancy measurement

line-focus

sized for general-purpose coil winding and electromagnet construction at the workhorse gauge of the line

and internal organelles for detailed protist biology teaching

Round Convex Glass Mirror, 75mm Diameter, 200mm Focal Length Material_Steel Wooden fulcrum-balance simple-machine model withConvex glass mirror at 75mm diameter and 200mm focal length, ~3. 1mm thick, the longer focal value softening divergence and producing a wider apparent field through reduced virtual reflections.