Springs

physics · machines · energy · everyday inventions

Bouncy energy storage. Springs soak up energy when you press, pull, or twist them, then let that energy go when you let go. It's like the spring remembers where it came from and wants to go back there.

Coils rule the world. Most springs you see are coil springs (shaped like a twisted spiral), but springs come in lots of designs depending on what job they need to do. They're hiding in chairs, cars, pens, and trampolines.

Made from spring steel. Modern springs are usually made from special spring steel that can bend thousands of times without breaking or getting tired. This steel is specially hardened to handle all that stretching and squishing.

Old-school springy wood. Before metal springs, people used flexible wood like yew to make bows that could store energy when drawn back and then launch arrows with a snap. Nature gave us springs long before we invented them.

Shape memory power. What makes springs special is their elastic material, which means they resist being bent or twisted but always want to return to their original shape. Once you stop the force, the spring snaps right back.