3-Piece Pendulum Bob Set with Hooks (Brass, Copper, Iron), 25mm Entomology & Zoology_Zoology Models demonstrating that sound requires a

demonstrating that sound requires a medium to propagate

and pendulum experiments at a larger ball scale

Four-diode bridge rectifier rated 5A at 100V with 4mm input connections and the circuit diagram printed on the case

Four-meter 6A extension cord with one 3-pin and three 2-pin sockets and a switched indicator-light handle

and a tensioning pulley

3-Piece Pendulum Bob Set with Hooks (Brass, Copper, Iron), 25mm Entomology & Zoology_Zoology Models demonstrating that sound requires aThree bob pendulum set with 1 inch brass, copper, and iron bobs, each with a removable threaded hook for mass and density comparison in pendulum period investigations.