The compound pulley made use of four ropes to lift the weight instead of a single rope. As a result, it was four times easier to lift the weight, but you had to pull four times as much rope. Dismantle the dome in the reverse order to which it was assembled. This experiment proves just how strong the dome shape is. This demonstrates compression and tension .
Compression is a pushing force - it squashes materials.
Look for materials in compression in tree trunks, pyramids, and arch bridges. Tension is a pulling force - it stretches materials. Look for materials in tension in telephone wires, suspension bridges, steel elevator cables, and inflated stadium domes. Perhaps, if you squeezed in the middle, but try squeezing the ends evenly between your hands. Produced by Galactics .