Concave Glass Mirror, 75mm Diameter, 100mm Focal Length Metal Labware_Metal Labware Sets 5-ohm reference coil non-inductively wound

5-ohm reference coil non-inductively wound from constantan on a 43mm ABS-supported bobbin with three 4mm sockets

designed to hold visible iron-filing field lines and support side-by-side magnet-strength comparisons in mechanics labs

supplied with weights and set up to minimize parallax error during spring-extension measurements

Supplied as the seven most common classroom sizes

Concave Glass Mirror, 75mm Diameter, 100mm Focal Length Metal Labware_Metal Labware Sets 5-ohm reference coil non-inductively woundPairs 75mm of aperture with a 100mm focal length on a concave glass surface, the f 1. 3 ratio giving fast convergence with moderate working distance for image formation work.