Spare 500g Iron Hooked Weight with Retractable Hook Subject_Astronomy 75-inch diameter pendulum bob with

75-inch diameter pendulum bob with a removable threaded hook

near-collimated for astronomical analogue and long-throw projection setups

Converts chemical energy to electrical through a zinc-copper-sulfate redox couple

the high-concentration AgNO3 reagent for halide-precipitation tests

the larger geometry pushing pole separation wide enough that field lines extend visibly beyond the magnet body for filing maps

Spare 500g Iron Hooked Weight with Retractable Hook Subject_Astronomy 75-inch diameter pendulum bob withCast iron 500g mass carries a retractable hook for suspension from spring scales, pulleys, or beams, serving as a replacement piece for gravitational and force measurement setups.