Forces in action
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6. Stretching a spring. Hooke´s law

Elasticity is the property of an object or material which causes it to be restored to its original shape after distortion.

• A spring is an example of an elastic object- when stretched, it exerts a restoring force which tends to bring it back to its original length.

Hooke’s Law: the restoring force is generally proportional to the amount of stretch.

Hookes´s Law

The extension or compresion (deformation) of an elastic body is directly proportional to the force applied to it.

There is a negative sign on the right-hand side of the equation because
the restoring force always acts in the opposite direction of the displacement
(for example, when a spring is stretched to the left, it pulls back to the right).

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