PHYSICS

Look at any bridge, crane, or tent and you are seeing physics in action. Structures must carry weight without collapsing. Engineers study two especially important internal forces. Tension is a pulling force that tries to stretch a material, like a rope in a tug-of-war. Compression is a squeezing force that tries to shorten or crush a material, like pressing a sponge. Real buildings use both at once. Cables and steel wires are brilliant in tension because they resist being pulled apart. Stone, concrete, and thick steel columns handle compression well because they resist being squashed. Smart design puts each material where it works best.