Stretching and Squeezing

Springs are used in a variety of ways. They can be squashed or stretched. A squashed spring pushes up with the same amount of force that squashes it down. A stretched spring pulls back with the same amount of force that stretches it. If you stretch a spring too far it will not go back to shape.





BOING! Springs are all around us - most are made from a spiral of metal. There are big springs on trampolines and tiny springs in pens.



THAT'S THE LIMIT You can't stretch a spring forever! When you compress or squeeze a spring you push the particles it is made from closer together. When you let it go, they jump apart. An elastic band is a bit like a spring. If you extend or stretch it you can feel the force pulling back on your hands. If you let it go, it will spring back to its original shape. But if you keep on stretching, it will not go back to shape. It may snap! This is its "elastic limit". Force is measure in NEWTONS IN = 1newton