US$ 710.50
varying length isolating density as the single variable across materials
this concave glass mirror at 100mm focal length runs at f/1 for vivid real-image demos and converging-reflection work
Acrylic bell-in-vacuum jar with an internal 4-6V DC electric bell that fades and falls silent as the enclosed air is removed
packaged in a wooden storage box
Bell in Vacuum Jar, Acrylic, 4-6V DC Pack Size_100 varying length isolating density asAcrylic bell in vacuum jar with an internal 4 6V DC electric bell that fades and falls silent as the enclosed air is removed, visualizing sound transmission dependence on a medium.
US$ 710.50
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