Spring (device)

Other types include:

Theory

In classical physics, a spring can be seen as a device that stores potential energy by straining the bonds between the atoms of an
elastic material.

Hooke's law of elasticity states that the extension of an elastic rod (its distended length minus its relaxed length) is linearly proportional to its tension, the force used to stretch it. Similarly, the contraction (negative extension) is proportional to the compression (negative tension).

This law actually holds only approximately, when the deformation (extension or contraction) is small compared to the rod's overall length. For large enough deformations, the atom bonds get broken or rearranged, and the rod may snap, buckle, or permanently deform. Even if that limit is not reached, the force may deviate noticeably from Hooke's law.

Hooke's law is actually a mathematical consequence of the fact that the potential energy of the rod is a minimum when it has its relaxed length. Any smooth function of one variable approximates a quadratic function when examined near enough to its minimum point; and therefore the force — which is the derivative of energy with respect to displacement — will approximate a linear function.

Custom fabrication of springs

Toys

See: Slinky

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