Copper and Iron Compound Bar for Thermal Expansion Material_Glass Illustrates liquid-density changes with temperature

Illustrates liquid-density changes with temperature using a weighted 75mm hollow copper sphere that floats in 15°C water and sinks as the water warms to 30°C

and concentrated oxidizer monitoring in water-treatment workflows

Hard vulcanized ebonite rod that takes on a strong negative charge when rubbed with fur

running on cone bearings in a cord-ready metal frame for friction

the thinnest gauge for mounting the smallest and most delicate insect specimens in permanent displays

Copper and Iron Compound Bar for Thermal Expansion Material_Glass Illustrates liquid-density changes with temperatureRiveted compound bar of copper and iron strips at 200 by 15mm, flexing under heat as each metal expands at a different rate, the working principle behind bimetallic thermostats.